1QString(3qt) QString(3qt)
2
6 QString - Abstraction of Unicode text and the classic C
7 '\0'-terminated char array
8
10 All the functions in this class are reentrant when Qt is built with
11 thread support.</p>
12 #include <qstring.h>
14 Public Members
16 QString ()
17 QString ( QChar ch )
18 QString ( const QString & s )
19 QString ( const QByteArray & ba )
20 QString ( const QChar * unicode, uint length )
21 QString ( const char * str )
22 QString ( const std::string & str )
23 ~QString ()
24 QString & operator= ( const QString & s )
25 QString & operator= ( const char * str )
26 QString & operator= ( const std::string & s )
27 QString & operator= ( const QCString & cstr )
28 QString & operator= ( QChar c )
29 QString & operator= ( char c )
30 bool isNull () const
31 bool isEmpty () const
32 uint length () const
33 void truncate ( uint newLen )
34 QString & fill ( QChar c, int len = -1 )
35 QString copy () const (obsolete)
36 QString arg ( long a, int fieldWidth = 0, int base = 10 ) const
37 QString arg ( ulong a, int fieldWidth = 0, int base = 10 ) const
38 QString arg ( Q_LLONG a, int fieldWidth = 0, int base = 10 ) const
39 QString arg ( Q_ULLONG a, int fieldWidth = 0, int base = 10 ) const
40 QString arg ( int a, int fieldWidth = 0, int base = 10 ) const
41 QString arg ( uint a, int fieldWidth = 0, int base = 10 ) const
42 QString arg ( short a, int fieldWidth = 0, int base = 10 ) const
43 QString arg ( ushort a, int fieldWidth = 0, int base = 10 ) const
44 QString arg ( double a, int fieldWidth = 0, char fmt = 'g', int prec =
45 -1 ) const
46 QString arg ( char a, int fieldWidth = 0 ) const
47 QString arg ( QChar a, int fieldWidth = 0 ) const
48 QString arg ( const QString & a, int fieldWidth = 0 ) const
49 QString arg ( const QString & a1, const QString & a2 ) const
50 QString arg ( const QString & a1, const QString & a2, const QString &
51 a3 ) const
52 QString arg ( const QString & a1, const QString & a2, const QString &
53 a3, const QString & a4 ) const
54 QString & sprintf ( const char * cformat, ... )
55 int find ( QChar c, int index = 0, bool cs = TRUE ) const
56 int find ( char c, int index = 0, bool cs = TRUE ) const
57 int find ( const QString & str, int index = 0, bool cs = TRUE ) const
58 int find ( const QRegExp & rx, int index = 0 ) const
59 int find ( const char * str, int index = 0 ) const
60 int findRev ( QChar c, int index = -1, bool cs = TRUE ) const
61 int findRev ( char c, int index = -1, bool cs = TRUE ) const
62 int findRev ( const QString & str, int index = -1, bool cs = TRUE )
63 const
64 int findRev ( const QRegExp & rx, int index = -1 ) const
65 int findRev ( const char * str, int index = -1 ) const
66 int contains ( QChar c, bool cs = TRUE ) const
67 int contains ( char c, bool cs = TRUE ) const
68 int contains ( const char * str, bool cs = TRUE ) const
69 int contains ( const QString & str, bool cs = TRUE ) const
70 int contains ( const QRegExp & rx ) const
71 enum SectionFlags { SectionDefault = 0x00, SectionSkipEmpty = 0x01,
72 SectionIncludeLeadingSep = 0x02, SectionIncludeTrailingSep = 0x04,
73 SectionCaseInsensitiveSeps = 0x08 }
74 QString section ( QChar sep, int start, int end = 0xffffffff, int flags
75 = SectionDefault ) const
76 QString section ( char sep, int start, int end = 0xffffffff, int flags
77 = SectionDefault ) const
78 QString section ( const char * sep, int start, int end = 0xffffffff,
79 int flags = SectionDefault ) const
80 QString section ( const QString & sep, int start, int end = 0xffffffff,
81 int flags = SectionDefault ) const
82 QString section ( const QRegExp & reg, int start, int end = 0xffffffff,
83 int flags = SectionDefault ) const
84 QString left ( uint len ) const
85 QString right ( uint len ) const
86 QString mid ( uint index, uint len = 0xffffffff ) const
87 QString leftJustify ( uint width, QChar fill = ' ', bool truncate =
88 FALSE ) const
89 QString rightJustify ( uint width, QChar fill = ' ', bool truncate =
90 FALSE ) const
91 QString lower () const
92 QString upper () const
93 QString stripWhiteSpace () const
94 QString simplifyWhiteSpace () const
95 QString & insert ( uint index, const QString & s )
96 QString & insert ( uint index, const QByteArray & s )
97 QString & insert ( uint index, const char * s )
98 QString & insert ( uint index, const QChar * s, uint len )
99 QString & insert ( uint index, QChar c )
100 QString & insert ( uint index, char c )
101 QString & append ( char ch )
102 QString & append ( QChar ch )
103 QString & append ( const QString & str )
104 QString & append ( const QByteArray & str )
105 QString & append ( const char * str )
106 QString & append ( const std::string & str )
107 QString & prepend ( char ch )
108 QString & prepend ( QChar ch )
109 QString & prepend ( const QString & s )
110 QString & prepend ( const QByteArray & s )
111 QString & prepend ( const char * s )
112 QString & prepend ( const std::string & s )
113 QString & remove ( uint index, uint len )
114 QString & remove ( const QString & str, bool cs = TRUE )
115 QString & remove ( QChar c )
116 QString & remove ( char c )
117 QString & remove ( const char * str )
118 QString & remove ( const QRegExp & rx )
119 QString & replace ( uint index, uint len, const QString & s )
120 QString & replace ( uint index, uint len, const QChar * s, uint slen )
121 QString & replace ( uint index, uint len, QChar c )
122 QString & replace ( uint index, uint len, char c )
123 QString & replace ( QChar c, const QString & after, bool cs = TRUE )
124 QString & replace ( char c, const QString & after, bool cs = TRUE )
125 QString & replace ( const QString & before, const QString & after, bool
126 cs = TRUE )
127 QString & replace ( const QRegExp & rx, const QString & after )
128 QString & replace ( QChar c1, QChar c2 )
129 short toShort ( bool * ok = 0, int base = 10 ) const
130 ushort toUShort ( bool * ok = 0, int base = 10 ) const
131 int toInt ( bool * ok = 0, int base = 10 ) const
132 uint toUInt ( bool * ok = 0, int base = 10 ) const
133 long toLong ( bool * ok = 0, int base = 10 ) const
134 ulong toULong ( bool * ok = 0, int base = 10 ) const
135 Q_LLONG toLongLong ( bool * ok = 0, int base = 10 ) const
136 Q_ULLONG toULongLong ( bool * ok = 0, int base = 10 ) const
137 float toFloat ( bool * ok = 0 ) const
138 double toDouble ( bool * ok = 0 ) const
139 QString & setNum ( short n, int base = 10 )
140 QString & setNum ( ushort n, int base = 10 )
141 QString & setNum ( int n, int base = 10 )
142 QString & setNum ( uint n, int base = 10 )
143 QString & setNum ( long n, int base = 10 )
144 QString & setNum ( ulong n, int base = 10 )
145 QString & setNum ( Q_LLONG n, int base = 10 )
146 QString & setNum ( Q_ULLONG n, int base = 10 )
147 QString & setNum ( float n, char f = 'g', int prec = 6 )
148 QString & setNum ( double n, char f = 'g', int prec = 6 )
149 void setExpand ( uint index, QChar c ) (obsolete)
150 QString & operator+= ( const QString & str )
151 QString & operator+= ( const QByteArray & str )
152 QString & operator+= ( const char * str )
153 QString & operator+= ( const std::string & str )
154 QString & operator+= ( QChar c )
155 QString & operator+= ( char c )
156 QChar at ( uint i ) const
157 QChar operator[] ( int i ) const
158 QCharRef at ( uint i )
159 QCharRef operator[] ( int i )
160 QChar constref ( uint i ) const
161 QChar & ref ( uint i )
162 const QChar * unicode () const
163 const char * ascii () const
164 const char * latin1 () const
165 QCString utf8 () const
166 QCString local8Bit () const
167 bool operator! () const
168 operator const char * () const
169 operator std::string () const
170 const unsigned short * ucs2 () const
171 QString & setUnicode ( const QChar * unicode, uint len )
172 QString & setUnicodeCodes ( const ushort * unicode_as_ushorts, uint len
173 )
174 QString & setAscii ( const char * str, int len = -1 )
175 QString & setLatin1 ( const char * str, int len = -1 )
176 int compare ( const QString & s ) const
177 int localeAwareCompare ( const QString & s ) const
178 void compose ()
179 const char * data () const (obsolete)
180 bool startsWith ( const QString & s, bool cs = TRUE ) const
181 bool endsWith ( const QString & s, bool cs = TRUE ) const
182 void setLength ( uint newLen )
183 uint capacity () const
184 void reserve ( uint minCapacity )
185 void squeeze ()
186 Static Public Members
188 QString number ( long n, int base = 10 )
189 QString number ( ulong n, int base = 10 )
190 QString number ( Q_LLONG n, int base = 10 )
191 QString number ( Q_ULLONG n, int base = 10 )
192 QString number ( int n, int base = 10 )
193 QString number ( uint n, int base = 10 )
194 QString number ( double n, char f = 'g', int prec = 6 )
195 QString fromAscii ( const char * ascii, int len = -1 )
196 QString fromLatin1 ( const char * chars, int len = -1 )
197 QString fromUtf8 ( const char * utf8, int len = -1 )
198 QString fromLocal8Bit ( const char * local8Bit, int len = -1 )
199 QString fromUcs2 ( const unsigned short * str )
200 int compare ( const QString & s1, const QString & s2 )
201 int localeAwareCompare ( const QString & s1, const QString & s2 )
202
204 bool operator== ( const QString & s1, const QString & s2 )
205 bool operator== ( const QString & s1, const char * s2 )
206 bool operator== ( const char * s1, const QString & s2 )
207 bool operator!= ( const QString & s1, const QString & s2 )
208 bool operator!= ( const QString & s1, const char * s2 )
209 bool operator!= ( const char * s1, const QString & s2 )
210 bool operator< ( const QString & s1, const char * s2 )
211 bool operator< ( const char * s1, const QString & s2 )
212 bool operator<= ( const QString & s1, const char * s2 )
213 bool operator<= ( const char * s1, const QString & s2 )
214 bool operator> ( const QString & s1, const char * s2 )
215 bool operator> ( const char * s1, const QString & s2 )
216 bool operator>= ( const QString & s1, const char * s2 )
217 bool operator>= ( const char * s1, const QString & s2 )
218 const QString operator+ ( const QString & s1, const QString & s2 )
219 const QString operator+ ( const QString & s1, const char * s2 )
220 const QString operator+ ( const char * s1, const QString & s2 )
221 const QString operator+ ( const QString & s, char c )
222 const QString operator+ ( char c, const QString & s )
223 QDataStream & operator<< ( QDataStream & s, const QString & str )
224 QDataStream & operator>> ( QDataStream & s, QString & str )
225
227 The QString class provides an abstraction of Unicode text and the
228 classic C '\0'-terminated char array.
229 QString uses implicit sharing, which makes it very efficient and easy
231 to use.
232 In all of the QString methods that take const char * parameters, the
234 const char * is interpreted as a classic C-style '\0'-terminated
235 ASCII string. It is legal for the const char * parameter to be 0. If
236 the const char * is not '\0'-terminated, the results are undefined.
237 Functions that copy classic C strings into a QString will not copy the
238 terminating '\0' character. The QChar array of the QString (as
239 returned by unicode()) is generally not terminated by a '\0'. If
240 you need to pass a QString to a function that requires a C
241 '\0'-terminated string use latin1().
242 A QString that has not been assigned to anything is null, i.e. both the
244 length and data pointer is 0. A QString that references the empty
245 string ("", a single '\0' char) is empty. Both null and empty
246 QStrings are legal parameters to the methods. Assigning (const char *)
247 0 to QString gives a null QString. For convenience, QString::null is a
248 null QString. When sorting, empty strings come first, followed by non-
249 empty strings, followed by null strings. We recommend using if (
250 !str.isNull() ) to check for a non-null string rather than if ( !str );
251 see operator!() for an explanation.
252 Note that if you find that you are mixing usage of QCString, QString,
254 and QByteArray, this causes lots of unnecessary copying and might
255 indicate that the true nature of the data you are dealing with is
256 uncertain. If the data is '\0'-terminated 8-bit data, use QCString;
257 if it is unterminated (i.e. contains '\0's) 8-bit data, use
258 QByteArray; if it is text, use QString.
259 Lists of strings are handled by the QStringList class. You can split a
261 string into a list of strings using QStringList::split(), and join a
262 list of strings into a single string with an optional separator using
263 QStringList::join(). You can obtain a list of strings from a string
264 list that contain a particular substring or that match a particular
265 regex using QStringList::grep().
266 Note for C programmers
268 Due to C++'s type system and the fact that QString is implicitly
270 shared, QStrings can be treated like ints or other simple base types.
271 For example:
272 QString boolToString( bool b )
274 {
275 QString result;
276 if ( b )
277 result = "True";
278 else
279 result = "False";
280 return result;
281 }
282 The variable, result, is an auto variable allocated on the stack. When
284 return is called, because we're returning by value, The copy
285 constructor is called and a copy of the string is returned. (No actual
286 copying takes place thanks to the implicit sharing, see below.)
287 Throughout Qt's source code you will encounter QString usages like
289 this:
290 QString func( const QString& input )
292 {
293 QString output = input;
294 // process output
295 return output;
296 }
297 The 'copying' of input to output is almost as fast as copying a pointer
299 because behind the scenes copying is achieved by incrementing a
300 reference count. QString (like all Qt's implicitly shared classes)
301 operates on a copy-on-write basis, only copying if an instance is
302 actually changed.
303 If you wish to create a deep copy of a QString without losing any
305 Unicode information then you should use QDeepCopy.
306 See also QChar, QCString, QByteArray, QConstString, Implicitly and
308 Explicitly Shared Classes, Text Related Classes, and Non-GUI Classes.
309 Member Type Documentation
312 QString::SectionDefault - Empty fields are counted, leading and
313 trailing separators are not included, and the separator is compared
314 case sensitively.
315 QString::SectionSkipEmpty - Treat empty fields as if they don't exist,
317 i.e. they are not considered as far as start and end are concerned.
318 QString::SectionIncludeLeadingSep - Include the leading separator (if
320 any) in the result string.
321 QString::SectionIncludeTrailingSep - Include the trailing separator (if
323 any) in the result string.
324 QString::SectionCaseInsensitiveSeps - Compare the separator case-
326 insensitively.
327 Any of the last four values can be OR-ed together to form a flag.
329 See also section().
331
334 Constructs a null string, i.e. both the length and data pointer are 0.
335 See also isNull().
337
339 Constructs a string of length one, containing the character ch.
340
342 Constructs an implicitly shared copy of s. This is very fast since it
343 only involves incrementing a reference count.
344
346 Constructs a string that is a deep copy of ba interpreted as a classic
347 C string.
348
350 Constructs a string that is a deep copy of the first length characters
351 in the QChar array.
352 If unicode and length are 0, then a null string is created.
354 If only unicode is 0, the string is empty but has length characters of
356 space preallocated: QString expands automatically anyway, but this may
357 speed up some cases a little. We recommend using the plain constructor
358 and setLength() for this purpose since it will result in more readable
359 code.
360 See also isNull() and setLength().
362
364 Constructs a string that is a deep copy of str, interpreted as a
365 classic C string. The encoding is assumed to be Latin-1, unless you
366 change it using QTextCodec::setCodecForCStrings().
367 If str is 0, then a null string is created.
369 This is a cast constructor, but it is perfectly safe: converting a
371 Latin-1 const char * to QString preserves all the information. You can
372 disable this constructor by defining QT_NO_CAST_ASCII when you compile
373 your applications. You can also make QString objects by using
374 setLatin1(), fromLatin1(), fromLocal8Bit(), and fromUtf8(). Or whatever
375 encoding is appropriate for the 8-bit data you have.
376 See also isNull() and fromAscii().
378
380 Constructs a string that is a deep copy of str.
381 This is the same as fromAscii(str).
383
385 Destroys the string and frees the string's data if this is the last
386 reference to the string.
387
389 Appends str to the string and returns a reference to the result.
390 string = "Test";
392 string.append( "ing" ); // string == "Testing"
393 Equivalent to operator+=().
395 Example: dirview/dirview.cpp.
397
399 This is an overloaded member function, provided for convenience. It
400 behaves essentially like the above function.
401 Appends character ch to the string and returns a reference to the
403 result.
404 Equivalent to operator+=().
406
408 This is an overloaded member function, provided for convenience. It
409 behaves essentially like the above function.
410 Appends character ch to the string and returns a reference to the
412 result.
413 Equivalent to operator+=().
415
417 This is an overloaded member function, provided for convenience. It
418 behaves essentially like the above function.
419 Appends str to the string and returns a reference to the result.
421 Equivalent to operator+=().
423
425 This is an overloaded member function, provided for convenience. It
426 behaves essentially like the above function.
427 Appends str to the string and returns a reference to the result.
429 Equivalent to operator+=().
431
433 This is an overloaded member function, provided for convenience. It
434 behaves essentially like the above function.
435 Appends str to the string and returns a reference to the result.
437 Equivalent to operator+=().
439
441 This function will return a string that replaces the lowest numbered
442 occurrence of %1, %2, ..., %9 with a.
443 The fieldWidth value specifies the minimum amount of space that a is
445 padded to. A positive value will produce right-aligned text, whereas a
446 negative value will produce left-aligned text.
447 The following example shows how we could create a 'status' string when
449 processing a list of files:
450 QString status = QString( "Processing file %1 of %2: %3" )
452 .arg( i ) // current file's number
453 .arg( total ) // number of files to process
454 .arg( fileName ); // current file's name
455 It is generally fine to use filenames and numbers as we have done in
457 the example above. But note that using arg() to construct natural
458 language sentences does not usually translate well into other languages
459 because sentence structure and word order often differ between
460 languages.
461 If there is no place marker (%1, %2, etc.), a warning message
463 (qWarning()) is output and the result is undefined.
464 Warning: If any placeholder occurs more than once, the result is
466 undefined.
467
469 This is an overloaded member function, provided for convenience. It
470 behaves essentially like the above function.
471 The fieldWidth value specifies the minimum amount of space that a is
473 padded to. A positive value will produce a right-aligned number,
474 whereas a negative value will produce a left-aligned number.
475 a is expressed in base base, which is 10 by default and must be between
477 2 and 36.
478 The '%' can be followed by an 'L', in which case the sequence is
480 replaced with a localized representation of a. The conversion uses the
481 default locale. The default locale is determined from the system's
482 locale settings at application startup. It can be changed using
483 QLocale::setDefault(). The 'L' flag is ignored if base is not 10.
484 QString str;
486 str = QString( "Decimal 63 is %1 in hexadecimal" )
487 .arg( 63, 0, 16 );
488 // str == "Decimal 63 is 3f in hexadecimal"
489 QLocale::setDefault(QLocale::English, QLocale::UnitedStates);
490 str = QString( "%1 %L2 %L3" )
491 .arg( 12345 )
492 .arg( 12345 )
493 .arg( 12345, 0, 16 );
494 // str == "12345 12,345 3039"
495
497 This is an overloaded member function, provided for convenience. It
498 behaves essentially like the above function.
499 a is expressed in base base, which is 10 by default and must be between
501 2 and 36. If base is 10, the '%L' syntax can be used to produce
502 localized strings.
503
505 This is an overloaded member function, provided for convenience. It
506 behaves essentially like the above function.
507 a is expressed in base base, which is 10 by default and must be between
509 2 and 36. If base is 10, the '%L' syntax can be used to produce
510 localized strings.
511
513 This is an overloaded member function, provided for convenience. It
514 behaves essentially like the above function.
515 a is expressed in base base, which is 10 by default and must be between
517 2 and 36. If base is 10, the '%L' syntax can be used to produce
518 localized strings.
519
521 This is an overloaded member function, provided for convenience. It
522 behaves essentially like the above function.
523 a is expressed in base base, which is 10 by default and must be between
525 2 and 36. If base is 10, the '%L' syntax can be used to produce
526 localized strings.
527
529 This is an overloaded member function, provided for convenience. It
530 behaves essentially like the above function.
531 a is expressed in base base, which is 10 by default and must be between
533 2 and 36. If base is 10, the '%L' syntax can be used to produce
534 localized strings.
535
537 This is an overloaded member function, provided for convenience. It
538 behaves essentially like the above function.
539 a is expressed in base base, which is 10 by default and must be between
541 2 and 36. If base is 10, the '%L' syntax can be used to produce
542 localized strings.
543
545 This is an overloaded member function, provided for convenience. It
546 behaves essentially like the above function.
547 a is expressed in base base, which is 10 by default and must be between
549 2 and 36. If base is 10, the '%L' syntax can be used to produce
550 localized strings.
551
553 = -1 ) const
554 This is an overloaded member function, provided for convenience. It
555 behaves essentially like the above function.
556 Argument a is formatted according to the fmt format specified, which is
558 'g' by default and can be any of the following:
559 <center>.nf
561 </center>
563 With 'e', 'E', and 'f', prec is the number of digits after the decimal
565 point. With 'g' and 'G', prec is the maximum number of significant
566 digits (trailing zeroes are omitted).
567 double d = 12.34;
569 QString ds = QString( "'E' format, precision 3, gives %1" )
570 .arg( d, 0, 'E', 3 );
571 // ds == "'E' format, precision 3, gives 1.234E+01"
572 The '%L' syntax can be used to produce localized strings.
574
576 This is an overloaded member function, provided for convenience. It
577 behaves essentially like the above function.
578 a is assumed to be in the Latin-1 character set.
580
582 This is an overloaded member function, provided for convenience. It
583 behaves essentially like the above function.
584
586 This is an overloaded member function, provided for convenience. It
587 behaves essentially like the above function.
588 This is the same as str.arg(a1).arg(a2), except that the strings are
590 replaced in one pass. This can make a difference if a1 contains e.g.
591 %1:
592 QString str( "%1 %2" );
594 str.arg( "Hello", "world" ); // returns "Hello world"
595 str.arg( "Hello" ).arg( "world" ); // returns "Hello world"
596 str.arg( "(%1)", "Hello" ); // returns "(%1) Hello"
597 str.arg( "(%1)" ).arg( "Hello" ); // returns "(Hello) %2"
598
600 a3 ) const
601 This is an overloaded member function, provided for convenience. It
602 behaves essentially like the above function.
603 This is the same as calling str.arg(a1).arg(a2).arg(a3), except that
605 the strings are replaced in one pass.
606
608 a3, const QString & a4 ) const
609 This is an overloaded member function, provided for convenience. It
610 behaves essentially like the above function.
611 This is the same as calling str.arg(a1).arg(a2).arg(a3).arg(a4), except
613 that the strings are replaced in one pass.
614
616 Returns an 8-bit ASCII representation of the string.
617 If a codec has been set using QTextCodec::codecForCStrings(), it is
619 used to convert Unicode to 8-bit char. Otherwise, this function does
620 the same as latin1().
621 See also fromAscii(), latin1(), utf8(), and local8Bit().
623 Example: network/networkprotocol/nntp.cpp.
625
627 Returns the character at index i, or 0 if i is beyond the length of the
628 string.
629 const QString string( "abcdefgh" );
631 QChar ch = string.at( 4 );
632 // ch == 'e'
633 If the QString is not const (i.e. const QString) or const& (i.e. const
635 QString &), then the non-const overload of at() will be used instead.
636
638 This is an overloaded member function, provided for convenience. It
639 behaves essentially like the above function.
640 The function returns a reference to the character at index i. The
642 resulting reference can then be assigned to, or used immediately, but
643 it will become invalid once further modifications are made to the
644 original string.
645 If i is beyond the length of the string then the string is expanded
647 with QChar::null.
648
650 Returns the number of characters this string can hold in the allocated
651 memory.
652 See also reserve() and squeeze().
654
656 Lexically compares s1 with s2 and returns an integer less than, equal
657 to, or greater than zero if s1 is less than, equal to, or greater than
658 s2.
659 The comparison is based exclusively on the numeric Unicode values of
661 the characters and is very fast, but is not what a human would expect.
662 Consider sorting user-interface strings with
663 QString::localeAwareCompare().
664 int a = QString::compare( "def", "abc" ); // a > 0
666 int b = QString::compare( "abc", "def" ); // b < 0
667 int c = QString::compare( "abc", "abc" ); // c == 0
668
670 This is an overloaded member function, provided for convenience. It
671 behaves essentially like the above function.
672 Lexically compares this string with s and returns an integer less than,
674 equal to, or greater than zero if it is less than, equal to, or greater
675 than s.
676
678 Warning: This function is not supported in Qt 3.x. It is provided for
679 experimental and illustrative purposes only. It is mainly of interest
680 to those experimenting with Arabic and other composition-rich texts.
681 Applies possible ligatures to a QString. Useful when composition-rich
683 text requires rendering with glyph-poor fonts, but it also makes
684 compositions such as QChar(0x0041) ('A') and QChar(0x0308) (Unicode
685 accent diaresis), giving QChar(0x00c4) (German A Umlaut).
686
688 Returns the QChar at index i by value.
689 Equivalent to at(i).
691 See also ref().
693
695 Returns the number of times the character c occurs in the string.
696 If cs is TRUE (the default), the search is case sensitive; otherwise
698 the search is case insensitive.
699 QString string( "Trolltech and Qt" );
701 int n = string.contains( 't', FALSE );
702 // n == 3
703 Examples:
705
707 This is an overloaded member function, provided for convenience. It
708 behaves essentially like the above function.
709
711 This is an overloaded member function, provided for convenience. It
712 behaves essentially like the above function.
713 Returns the number of times the string str occurs in the string.
715 If cs is TRUE (the default), the search is case sensitive; otherwise
717 the search is case insensitive.
718
720 This is an overloaded member function, provided for convenience. It
721 behaves essentially like the above function.
722 Returns the number of times str occurs in the string.
724 If cs is TRUE (the default), the search is case sensitive; otherwise
726 the search is case insensitive.
727 This function counts overlapping strings, so in the example below,
729 there are two instances of "ana" in "bananas".
730 QString str( "bananas" );
732 int i = str.contains( "ana" ); // i == 2
733 See also findRev().
735
737 This is an overloaded member function, provided for convenience. It
738 behaves essentially like the above function.
739 Returns the number of times the regexp, rx, matches in the string.
741 This function counts overlapping matches, so in the example below,
743 there are four instances of "ana" or "ama".
744 QString str = "banana and panama";
746 QRegExp rxp = QRegExp( "a[nm]a", TRUE, FALSE );
747 int i = str.contains( rxp ); // i == 4
748 See also find() and findRev().
750
752 This function is obsolete. It is provided to keep old source working.
753 We strongly advise against using it in new code.
754 In Qt 2.0 and later, all calls to this function are needless. Just
756 remove them.
757
759 This function is obsolete. It is provided to keep old source working.
760 We strongly advise against using it in new code.
761 Returns a pointer to a '\0'-terminated classic C string.
763 In Qt 1.x, this returned a char* allowing direct manipulation of the
765 string as a sequence of bytes. In Qt 2.x where QString is a Unicode
766 string, char* conversion constructs a temporary string, and hence
767 direct character operations are meaningless.
768
770 Returns TRUE if the string ends with s; otherwise returns FALSE.
771 If cs is TRUE (the default), the search is case sensitive; otherwise
773 the search is case insensitive.
774 QString str( "Bananas" );
776 str.endsWith( "anas" ); // returns TRUE
777 str.endsWith( "pple" ); // returns FALSE
778 See also startsWith().
780 Example: chart/main.cpp.
782
784 Fills the string with len characters of value c, and returns a
785 reference to the string.
786 If len is negative (the default), the current string length is used.
788 QString str;
790 str.fill( 'g', 5 ); // string == "ggggg"
791
793 Finds the first match of the regular expression rx, starting from
794 position index. If index is -1, the search starts at the last
795 character; if -2, at the next to last character and so on. (See
796 findRev() for searching backwards.)
797 Returns the position of the first match of rx or -1 if no match was
799 found.
800 QString string( "bananas" );
802 int i = string.find( QRegExp("an"), 0 ); // i == 1
803 See also findRev(), replace(), and contains().
805 Example: network/mail/smtp.cpp.
807
809 This is an overloaded member function, provided for convenience. It
810 behaves essentially like the above function.
811 Finds the first occurrence of the character c, starting at position
813 index. If index is -1, the search starts at the last character; if -2,
814 at the next to last character and so on. (See findRev() for searching
815 backwards.)
816 If cs is TRUE (the default), the search is case sensitive; otherwise
818 the search is case insensitive.
819 Returns the position of c or -1 if c could not be found.
821
823 This is an overloaded member function, provided for convenience. It
824 behaves essentially like the above function.
825 Find character c starting from position index.
827 If cs is TRUE (the default), the search is case sensitive; otherwise
829 the search is case insensitive.
830
832 This is an overloaded member function, provided for convenience. It
834 behaves essentially like the above function.
835 Finds the first occurrence of the string str, starting at position
837 index. If index is -1, the search starts at the last character, if it
838 is -2, at the next to last character and so on. (See findRev() for
839 searching backwards.)
840 If cs is TRUE (the default), the search is case sensitive; otherwise
842 the search is case insensitive.
843 Returns the position of str or -1 if str could not be found.
845
847 This is an overloaded member function, provided for convenience. It
848 behaves essentially like the above function.
849 Equivalent to find(QString(str), index).
851
853 Equivalent to findRev(QString(str), index).
854
856 This is an overloaded member function, provided for convenience. It
857 behaves essentially like the above function.
858 Finds the first occurrence of the character c, starting at position
860 index and searching backwards. If the index is -1, the search starts at
861 the last character, if it is -2, at the next to last character and so
862 on.
863 Returns the position of c or -1 if c could not be found.
865 If cs is TRUE (the default), the search is case sensitive; otherwise
867 the search is case insensitive.
868 QString string( "bananas" );
870 int i = string.findRev( 'a' ); // i == 5
871
873 This is an overloaded member function, provided for convenience. It
874 behaves essentially like the above function.
875 Find character c starting from position index and working backwards.
877 If cs is TRUE (the default), the search is case sensitive; otherwise
879 the search is case insensitive.
880
882 const
883 This is an overloaded member function, provided for convenience. It
884 behaves essentially like the above function.
885 Finds the first occurrence of the string str, starting at position
887 index and searching backwards. If the index is -1, the search starts at
888 the last character, if it is -2, at the next to last character and so
889 on.
890 Returns the position of str or -1 if str could not be found.
892 If cs is TRUE (the default), the search is case sensitive; otherwise
894 the search is case insensitive.
895 QString string("bananas");
897 int i = string.findRev( "ana" ); // i == 3
898
900 This is an overloaded member function, provided for convenience. It
901 behaves essentially like the above function.
902 Finds the first match of the regexp rx, starting at position index and
904 searching backwards. If the index is -1, the search starts at the last
905 character, if it is -2, at the next to last character and so on. (See
906 findRev() for searching backwards.)
907 Returns the position of the match or -1 if no match was found.
909 QString string( "bananas" );
911 int i = string.findRev( QRegExp("an") ); // i == 3
912 See also find().
914
916 Returns the Unicode string decoded from the first len bytes of ascii,
917 ignoring the rest of ascii. If len is -1 then the length of ascii is
918 used. If len is bigger than the length of ascii then it will use the
919 length of ascii.
920 If a codec has been set using QTextCodec::codecForCStrings(), it is
922 used to convert the string from 8-bit characters to Unicode. Otherwise,
923 this function does the same as fromLatin1().
924 This is the same as the QString(const char*) constructor, but you can
926 make that constructor invisible if you compile with the define
927 QT_NO_CAST_ASCII, in which case you can explicitly create a QString
928 from 8-bit ASCII text using this function.
929 QString str = QString::fromAscii( "123456789", 5 );
931 // str == "12345"
932
934 Returns the Unicode string decoded from the first len bytes of chars,
935 ignoring the rest of chars. If len is -1 then the length of chars is
936 used. If len is bigger than the length of chars then it will use the
937 length of chars.
938 See also fromAscii().
940 Examples:
942
944 [static]
945 Returns the Unicode string decoded from the first len bytes of
946 local8Bit, ignoring the rest of local8Bit. If len is -1 then the length
947 of local8Bit is used. If len is bigger than the length of local8Bit
948 then it will use the length of local8Bit.
949 QString str = QString::fromLocal8Bit( "123456789", 5 );
951 // str == "12345"
952 local8Bit is assumed to be encoded in a locale-specific format.
954 See QTextCodec for more diverse coding/decoding of Unicode strings.
956
958 Constructs a string that is a deep copy of str, interpreted as a UCS2
959 encoded, zero terminated, Unicode string.
960 If str is 0, then a null string is created.
962 See also isNull().
964
966 Returns the Unicode string decoded from the first len bytes of utf8,
967 ignoring the rest of utf8. If len is -1 then the length of utf8 is
968 used. If len is bigger than the length of utf8 then it will use the
969 length of utf8.
970 QString str = QString::fromUtf8( "123456789", 5 );
972 // str == "12345"
973 See QTextCodec for more diverse coding/decoding of Unicode strings.
975 Example: fonts/simple-qfont-demo/viewer.cpp.
977
979 Inserts s into the string at position index.
980 If index is beyond the end of the string, the string is extended with
982 spaces to length index and s is then appended and returns a reference
983 to the string.
984 QString string( "I like fish" );
986 str = string.insert( 2, "don't " );
987 // str == "I don't like fish"
988 See also remove() and replace().
990 Examples:
992
994 This is an overloaded member function, provided for convenience. It
995 behaves essentially like the above function.
996 Inserts s into the string at position index and returns a reference to
998 the string.
999
1001 This is an overloaded member function, provided for convenience. It
1002 behaves essentially like the above function.
1003 Inserts s into the string at position index and returns a reference to
1005 the string.
1006
1008 This is an overloaded member function, provided for convenience. It
1009 behaves essentially like the above function.
1010 Inserts the first len characters in s into the string at position index
1012 and returns a reference to the string.
1013
1015 This is an overloaded member function, provided for convenience. It
1016 behaves essentially like the above function.
1017 Insert c into the string at position index and returns a reference to
1019 the string.
1020 If index is beyond the end of the string, the string is extended with
1022 spaces (ASCII 32) to length index and c is then appended.
1023
1025 This is an overloaded member function, provided for convenience. It
1026 behaves essentially like the above function.
1027 Insert character c at position index.
1029
1031 Returns TRUE if the string is empty, i.e. if length() == 0; otherwise
1032 returns FALSE. Null strings are also empty.
1033 QString a( "" );
1035 a.isEmpty(); // TRUE
1036 a.isNull(); // FALSE
1037 QString b;
1038 b.isEmpty(); // TRUE
1039 b.isNull(); // TRUE
1040 See also isNull() and length().
1042 Examples:
1044
1046 Returns TRUE if the string is null; otherwise returns FALSE. A null
1047 string is always empty.
1048 QString a; // a.unicode() == 0, a.length() == 0
1050 a.isNull(); // TRUE, because a.unicode() == 0
1051 a.isEmpty(); // TRUE, because a.length() == 0
1052 See also isEmpty() and length().
1054 Examples:
1056
1058 Returns a Latin-1 representation of the string. The returned value is
1059 undefined if the string contains non-Latin-1 characters. If you want to
1060 convert strings into formats other than Unicode, see the QTextCodec
1061 classes.
1062 This function is mainly useful for boot-strapping legacy code to use
1064 Unicode.
1065 The result remains valid so long as one unmodified copy of the source
1067 string exists.
1068 See also fromLatin1(), ascii(), utf8(), and local8Bit().
1070 Examples:
1072
1074 Returns a substring that contains the len leftmost characters of the
1075 string.
1076 The whole string is returned if len exceeds the length of the string.
1078 QString s = "Pineapple";
1080 QString t = s.left( 4 ); // t == "Pine"
1081 See also right(), mid(), and isEmpty().
1083 Example: themes/themes.cpp.
1085
1087 FALSE ) const
1088 Returns a string of length width that contains this string padded by
1089 the fill character.
1090 If truncate is FALSE and the length of the string is more than width,
1092 then the returned string is a copy of the string.
1093 If truncate is TRUE and the length of the string is more than width,
1095 then any characters in a copy of the string after length width are
1096 removed, and the copy is returned.
1097 QString s( "apple" );
1099 QString t = s.leftJustify( 8, '.' ); // t == "apple..."
1100 See also rightJustify().
1102
1104 Returns the length of the string.
1105 Null strings and empty strings have zero length.
1107 See also isNull() and isEmpty().
1109 Examples:
1111
1113 Returns the string encoded in a locale-specific format. On X11, this is
1114 the QTextCodec::codecForLocale(). On Windows, it is a system-defined
1115 encoding. On Mac OS X, this always uses UTF-8 as the encoding.
1116 See QTextCodec for more diverse coding/decoding of Unicode strings.
1118 See also fromLocal8Bit(), ascii(), latin1(), and utf8().
1120
1122 [static]
1123 Compares s1 with s2 and returns an integer less than, equal to, or
1124 greater than zero if s1 is less than, equal to, or greater than s2.
1125 The comparison is performed in a locale- and also platform-dependent
1127 manner. Use this function to present sorted lists of strings to the
1128 user.
1129 See also QString::compare() and QTextCodec::locale().
1131
1133 This is an overloaded member function, provided for convenience. It
1134 behaves essentially like the above function.
1135 Compares this string with s.
1137
1139 Returns a lowercase copy of the string.
1140 QString string( "TROlltECH" );
1142 str = string.lower(); // str == "trolltech"
1143 See also upper().
1145 Example: scribble/scribble.cpp.
1147
1149 Returns a string that contains the len characters of this string,
1150 starting at position index.
1151 Returns a null string if the string is empty or index is out of range.
1153 Returns the whole string from index if index + len exceeds the length
1154 of the string.
1155 QString s( "Five pineapples" );
1157 QString t = s.mid( 5, 4 ); // t == "pine"
1158 See also left() and right().
1160 Examples:
1162
1164 A convenience function that returns a string equivalent of the number n
1165 to base base, which is 10 by default and must be between 2 and 36. The
1166 returned string is in "C" locale.
1167 long a = 63;
1169 QString str = QString::number( a, 16 ); // str == "3f"
1170 QString str = QString::number( a, 16 ).upper(); // str == "3F"
1171 See also setNum().
1173 Examples:
1175
1177 This is an overloaded member function, provided for convenience. It
1178 behaves essentially like the above function.
1179 See also setNum().
1181
1183 This is an overloaded member function, provided for convenience. It
1184 behaves essentially like the above function.
1185 See also setNum().
1187
1189 This is an overloaded member function, provided for convenience. It
1190 behaves essentially like the above function.
1191 See also setNum().
1193
1195 This is an overloaded member function, provided for convenience. It
1196 behaves essentially like the above function.
1197 See also setNum().
1199
1201 This is an overloaded member function, provided for convenience. It
1202 behaves essentially like the above function.
1203 A convenience factory function that returns a string representation of
1205 the number n to the base base, which is 10 by default and must be
1206 between 2 and 36.
1207 See also setNum().
1209
1211 This is an overloaded member function, provided for convenience. It
1212 behaves essentially like the above function.
1213 Argument n is formatted according to the f format specified, which is g
1215 by default, and can be any of the following:
1216 <center>.nf
1218 </center>
1220 With 'e', 'E', and 'f', prec is the number of digits after the decimal
1222 point. With 'g' and 'G', prec is the maximum number of significant
1223 digits (trailing zeroes are omitted).
1224 double d = 12.34;
1226 QString ds = QString( "'E' format, precision 3, gives %1" )
1227 .arg( d, 0, 'E', 3 );
1228 // ds == "1.234E+001"
1229 See also setNum().
1231
1233 Returns ascii(). Be sure to see the warnings documented in the ascii()
1234 function. Note that for new code which you wish to be strictly Unicode-
1235 clean, you can define the macro QT_NO_ASCII_CAST when compiling your
1236 code to hide this function so that automatic casts are not done. This
1237 has the added advantage that you catch the programming error described
1238 in operator!().
1239
1241 Returns ascii() as a std::string.
1242 Warning: The function may cause an application to crash if a static C
1244 run-time is in use. This can happen in Microsoft Visual C++ if Qt is
1245 configured as single-threaded. A safe alternative is to call ascii()
1246 directly and construct a std::string manually.
1247
1249 Returns TRUE if this is a null string; otherwise returns FALSE.
1250 QString name = getName();
1252 if ( !name )
1253 name = "Rodney";
1254 Note that if you say
1256 QString name = getName();
1258 if ( name )
1259 doSomethingWith(name);
1260 It will call "operator const char*()", which is inefficent; you may
1262 wish to define the macro QT_NO_ASCII_CAST when writing code which you
1263 wish to remain Unicode-clean.
1264 When you want the above semantics, use:
1266 QString name = getName();
1268 if ( !name.isNull() )
1269 doSomethingWith(name);
1270 See also isEmpty().
1272
1274 Appends str to the string and returns a reference to the string.
1275
1277 This is an overloaded member function, provided for convenience. It
1278 behaves essentially like the above function.
1279 Appends str to the string and returns a reference to the string.
1281
1283 This is an overloaded member function, provided for convenience. It
1284 behaves essentially like the above function.
1285 Appends str to the string and returns a reference to the string.
1287
1289 This is an overloaded member function, provided for convenience. It
1290 behaves essentially like the above function.
1291 Appends str to the string and returns a reference to the string.
1293
1295 This is an overloaded member function, provided for convenience. It
1296 behaves essentially like the above function.
1297 Appends c to the string and returns a reference to the string.
1299
1301 This is an overloaded member function, provided for convenience. It
1302 behaves essentially like the above function.
1303 Appends c to the string and returns a reference to the string.
1305
1307 Sets the string to contain just the single character c.
1308
1310 This is an overloaded member function, provided for convenience. It
1311 behaves essentially like the above function.
1312 Assigns a shallow copy of s to this string and returns a reference to
1314 this string. This is very fast because the string isn't actually
1315 copied.
1316
1318 This is an overloaded member function, provided for convenience. It
1319 behaves essentially like the above function.
1320 Assigns a deep copy of str, interpreted as a classic C string to this
1322 string and returns a reference to this string.
1323 If str is 0, then a null string is created.
1325 See also isNull().
1327
1329 This is an overloaded member function, provided for convenience. It
1330 behaves essentially like the above function.
1331 Makes a deep copy of s and returns a reference to the deep copy.
1333
1335 This is an overloaded member function, provided for convenience. It
1336 behaves essentially like the above function.
1337 Assigns a deep copy of cstr, interpreted as a classic C string, to this
1339 string. Returns a reference to this string.
1340
1342 This is an overloaded member function, provided for convenience. It
1343 behaves essentially like the above function.
1344 Sets the string to contain just the single character c.
1346
1348 Returns the character at index i, or QChar::null if i is beyond the
1349 length of the string.
1350 If the QString is not const (i.e., const QString) or const& (i.e.,
1352 const QString&), then the non-const overload of operator[] will be used
1353 instead.
1354
1356 This is an overloaded member function, provided for convenience. It
1357 behaves essentially like the above function.
1358 The function returns a reference to the character at index i. The
1360 resulting reference can then be assigned to, or used immediately, but
1361 it will become invalid once further modifications are made to the
1362 original string.
1363 If i is beyond the length of the string then the string is expanded
1365 with QChar::nulls, so that the QCharRef references a valid (null)
1366 character in the string.
1367 The QCharRef internal class can be used much like a constant QChar, but
1369 if you assign to it, you change the original string (which will detach
1370 itself because of QString's copy-on-write semantics). You will get
1371 compilation errors if you try to use the result as anything but a
1372 QChar.
1373
1375 Inserts s at the beginning of the string and returns a reference to the
1376 string.
1377 Equivalent to insert(0, s).
1379 QString string = "42";
1381 string.prepend( "The answer is " );
1382 // string == "The answer is 42"
1383 See also insert().
1385
1387 This is an overloaded member function, provided for convenience. It
1388 behaves essentially like the above function.
1389 Inserts ch at the beginning of the string and returns a reference to
1391 the string.
1392 Equivalent to insert(0, ch).
1394 See also insert().
1396
1398 This is an overloaded member function, provided for convenience. It
1399 behaves essentially like the above function.
1400 Inserts ch at the beginning of the string and returns a reference to
1402 the string.
1403 Equivalent to insert(0, ch).
1405 See also insert().
1407
1409 This is an overloaded member function, provided for convenience. It
1410 behaves essentially like the above function.
1411 Inserts s at the beginning of the string and returns a reference to the
1413 string.
1414 Equivalent to insert(0, s).
1416 See also insert().
1418
1420 This is an overloaded member function, provided for convenience. It
1421 behaves essentially like the above function.
1422 Inserts s at the beginning of the string and returns a reference to the
1424 string.
1425 Equivalent to insert(0, s).
1427 See also insert().
1429
1431 This is an overloaded member function, provided for convenience. It
1432 behaves essentially like the above function.
1433 Inserts s at the beginning of the string and returns a reference to the
1435 string.
1436 Equivalent to insert(0, s).
1438 See also insert().
1440
1442 Returns the QChar at index i by reference, expanding the string with
1443 QChar::null if necessary. The resulting reference can be assigned to,
1444 or otherwise used immediately, but becomes invalid once furher
1445 modifications are made to the string.
1446 QString string("ABCDEF");
1448 QChar ch = string.ref( 3 ); // ch == 'D'
1449 See also constref().
1451
1453 Removes len characters from the string starting at position index, and
1454 returns a reference to the string.
1455 If index is beyond the length of the string, nothing happens. If index
1457 is within the string, but index + len is beyond the end of the string,
1458 the string is truncated at position index.
1459 QString string( "Montreal" );
1461 string.remove( 1, 4 ); // string == "Meal"
1462 See also insert() and replace().
1464
1466 This is an overloaded member function, provided for convenience. It
1467 behaves essentially like the above function.
1468 Removes every occurrence of str in the string. Returns a reference to
1470 the string.
1471 If cs is TRUE (the default), the search is case sensitive; otherwise
1473 the search is case insensitive.
1474 This is the same as replace(str, "", cs).
1476
1478 This is an overloaded member function, provided for convenience. It
1479 behaves essentially like the above function.
1480 Removes every occurrence of the character c in the string. Returns a
1482 reference to the string.
1483 This is the same as replace(c, "").
1485
1487 This is an overloaded member function, provided for convenience. It
1488 behaves essentially like the above function.
1489 Removes every occurrence of the character c in the string. Returns a
1491 reference to the string.
1492 This is the same as replace(c, "").
1494
1496 This is an overloaded member function, provided for convenience. It
1497 behaves essentially like the above function.
1498 Removes every occurrence of str in the string. Returns a reference to
1500 the string.
1501
1503 This is an overloaded member function, provided for convenience. It
1504 behaves essentially like the above function.
1505 Removes every occurrence of the regular expression rx in the string.
1507 Returns a reference to the string.
1508 This is the same as replace(rx, "").
1510
1512 Replaces len characters from the string with s, starting at position
1513 index, and returns a reference to the string.
1514 If index is beyond the length of the string, nothing is deleted and s
1516 is appended at the end of the string. If index is valid, but index +
1517 len is beyond the end of the string, the string is truncated at
1518 position index, then s is appended at the end.
1519 QString string( "Say yes!" );
1521 string = string.replace( 4, 3, "NO" );
1522 // string == "Say NO!"
1523 Warning: Qt 3.3.3 and earlier had different semantics for the case
1525 index >= length(), which contradicted the documentation. To avoid
1526 portability problems between Qt 3 versions and with Qt 4, we recommend
1527 that you never call the function with index >= length().
1528 See also insert() and remove().
1530 Examples:
1532
1534 )
1535 This is an overloaded member function, provided for convenience. It
1536 behaves essentially like the above function.
1537 Replaces len characters with slen characters of QChar data from s,
1539 starting at position index, and returns a reference to the string.
1540 See also insert() and remove().
1542
1544 This is an overloaded member function, provided for convenience. It
1545 behaves essentially like the above function.
1546 This is the same as replace(index, len, QString(c)).
1548
1550 This is an overloaded member function, provided for convenience. It
1551 behaves essentially like the above function.
1552 This is the same as replace(index, len, QChar(c)).
1554
1556 This is an overloaded member function, provided for convenience. It
1557 behaves essentially like the above function.
1558 Replaces every occurrence of the character c in the string with after.
1560 Returns a reference to the string.
1561 If cs is TRUE (the default), the search is case sensitive; otherwise
1563 the search is case insensitive.
1564 Example:
1566 QString s = "a,b,c";
1568 s.replace( QChar(','), " or " );
1569 // s == "a or b or c"
1570
1572 This is an overloaded member function, provided for convenience. It
1573 behaves essentially like the above function.
1574 Replaces every occurrence of the character c in the string with after.
1576 Returns a reference to the string.
1577 If cs is TRUE (the default), the search is case sensitive; otherwise
1579 the search is case insensitive.
1580
1582 bool cs = TRUE )
1583 This is an overloaded member function, provided for convenience. It
1584 behaves essentially like the above function.
1585 Replaces every occurrence of the string before in the string with the
1587 string after. Returns a reference to the string.
1588 If cs is TRUE (the default), the search is case sensitive; otherwise
1590 the search is case insensitive.
1591 Example:
1593 QString s = "Greek is Greek";
1595 s.replace( "Greek", "English" );
1596 // s == "English is English"
1597
1599 This is an overloaded member function, provided for convenience. It
1600 behaves essentially like the above function.
1601 Replaces every occurrence of the regexp rx in the string with after.
1603 Returns a reference to the string. For example:
1604 QString s = "banana";
1606 s.replace( QRegExp("an"), "" );
1607 // s == "ba"
1608 For regexps containing capturing parentheses, occurrences of \1,
1610 \2, ..., in after are replaced with rx[24m.cap(1), cap(2), ...
1611 QString t = "A <i>bon mot</i>.";
1613 t.replace( QRegExp("<i>([^<]*)</i>"), "\\emph{\\1}" );
1614 // t == "A \\emph{bon mot}."
1615 See also find(), findRev(), and QRegExp::cap().
1617
1619 This is an overloaded member function, provided for convenience. It
1620 behaves essentially like the above function.
1621 Replaces every occurrence of c1 with the char c2. Returns a reference
1623 to the string.
1624
1626 Ensures that at least minCapacity characters are allocated to the
1627 string.
1628 This function is useful for code that needs to build up a long string
1630 and wants to avoid repeated reallocation. In this example, we want to
1631 add to the string until some condition is true, and we're fairly sure
1632 that size is big enough:
1633 QString result;
1635 int len = 0;
1636 result.reserve(maxLen);
1637 while (...) {
1638 result[len++] = ... // fill part of the space
1639 }
1640 result.squeeze();
1641 If maxLen is an underestimate, the worst that will happen is that the
1643 loop will slow down.
1644 If it is not possible to allocate enough memory, the string remains
1646 unchanged.
1647 See also capacity(), squeeze(), and setLength().
1649
1651 Returns a string that contains the len rightmost characters of the
1652 string.
1653 If len is greater than the length of the string then the whole string
1655 is returned.
1656 QString string( "Pineapple" );
1658 QString t = string.right( 5 ); // t == "apple"
1659 See also left(), mid(), and isEmpty().
1661 Example: fileiconview/qfileiconview.cpp.
1663
1665 FALSE ) const
1666 Returns a string of length width that contains the fill character
1667 followed by the string.
1668 If truncate is FALSE and the length of the string is more than width,
1670 then the returned string is a copy of the string.
1671 If truncate is TRUE and the length of the string is more than width,
1673 then the resulting string is truncated at position width.
1674 QString string( "apple" );
1676 QString t = string.rightJustify( 8, '.' ); // t == "...apple"
1677 See also leftJustify().
1679
1681 flags = SectionDefault ) const
1682 This function returns a section of the string.
1683 This string is treated as a sequence of fields separated by the
1685 character, sep. The returned string consists of the fields from
1686 position start to position end inclusive. If end is not specified, all
1687 fields from position start to the end of the string are included.
1688 Fields are numbered 0, 1, 2, etc., counting from the left, and -1, -2,
1689 etc., counting from right to left.
1690 The flags argument can be used to affect some aspects of the function's
1692 behaviour, e.g. whether to be case sensitive, whether to skip empty
1693 fields and how to deal with leading and trailing separators; see
1694 SectionFlags.
1695 QString csv( "forename,middlename,surname,phone" );
1697 QString s = csv.section( ',', 2, 2 ); // s == "surname"
1698 QString path( "/usr/local/bin/myapp" ); // First field is empty
1699 QString s = path.section( '/', 3, 4 ); // s == "bin/myapp"
1700 QString s = path.section( '/', 3, 3, SectionSkipEmpty ); // s == "myapp"
1701 If start or end is negative, we count fields from the right of the
1703 string, the right-most field being -1, the one from right-most field
1704 being -2, and so on.
1705 QString csv( "forename,middlename,surname,phone" );
1707 QString s = csv.section( ',', -3, -2 ); // s == "middlename,surname"
1708 QString path( "/usr/local/bin/myapp" ); // First field is empty
1709 QString s = path.section( '/', -1 ); // s == "myapp"
1710 See also QStringList::split().
1712 Examples:
1714
1716 flags = SectionDefault ) const
1717 This is an overloaded member function, provided for convenience. It
1718 behaves essentially like the above function.
1719
1721 int flags = SectionDefault ) const
1722 This is an overloaded member function, provided for convenience. It
1723 behaves essentially like the above function.
1724
1726 0xffffffff, int flags = SectionDefault ) const
1727 This is an overloaded member function, provided for convenience. It
1728 behaves essentially like the above function.
1729 This function returns a section of the string.
1731 This string is treated as a sequence of fields separated by the string,
1733 sep. The returned string consists of the fields from position start to
1734 position end inclusive. If end is not specified, all fields from
1735 position start to the end of the string are included. Fields are
1736 numbered 0, 1, 2, etc., counting from the left, and -1, -2, etc.,
1737 counting from right to left.
1738 The flags argument can be used to affect some aspects of the function's
1740 behaviour, e.g. whether to be case sensitive, whether to skip empty
1741 fields and how to deal with leading and trailing separators; see
1742 SectionFlags.
1743 QString data( "forename**middlename**surname**phone" );
1745 QString s = data.section( "**", 2, 2 ); // s == "surname"
1746 If start or end is negative, we count fields from the right of the
1748 string, the right-most field being -1, the one from right-most field
1749 being -2, and so on.
1750 QString data( "forename**middlename**surname**phone" );
1752 QString s = data.section( "**", -3, -2 ); // s == "middlename**surname"
1753 See also QStringList::split().
1755
1757 0xffffffff, int flags = SectionDefault ) const
1758 This is an overloaded member function, provided for convenience. It
1759 behaves essentially like the above function.
1760 This function returns a section of the string.
1762 This string is treated as a sequence of fields separated by the regular
1764 expression, reg. The returned string consists of the fields from
1765 position start to position end inclusive. If end is not specified, all
1766 fields from position start to the end of the string are included.
1767 Fields are numbered 0, 1, 2, etc., counting from the left, and -1, -2,
1768 etc., counting from right to left.
1769 The flags argument can be used to affect some aspects of the function's
1771 behaviour, e.g. whether to be case sensitive, whether to skip empty
1772 fields and how to deal with leading and trailing separators; see
1773 SectionFlags.
1774 QString line( "forename\tmiddlename surname \t \t phone" );
1776 QRegExp sep( "\s+" );
1777 QString s = line.section( sep, 2, 2 ); // s == "surname"
1778 If start or end is negative, we count fields from the right of the
1780 string, the right-most field being -1, the one from right-most field
1781 being -2, and so on.
1782 QString line( "forename\tmiddlename surname \t \t phone" );
1784 QRegExp sep( "\\s+" );
1785 QString s = line.section( sep, -3, -2 ); // s == "middlename surname"
1786 Warning: Using this QRegExp version is much more expensive than the
1788 overloaded string and character versions.
1789 See also QStringList::split() and simplifyWhiteSpace().
1791
1793 Sets this string to str, interpreted as a classic 8-bit ASCII C string.
1794 If len is -1 (the default), then it is set to strlen(str).
1795 If str is 0 a null string is created. If str is "", an empty string is
1797 created.
1798 See also isNull() and isEmpty().
1800
1802 This function is obsolete. It is provided to keep old source working.
1803 We strongly advise against using it in new code.
1804 Sets the character at position index to c and expands the string if
1806 necessary, filling with spaces.
1807 This method is redundant in Qt 3.x, because operator[] will expand the
1809 string as necessary.
1810
1812 Sets this string to str, interpreted as a classic Latin-1 C string. If
1813 len is -1 (the default), then it is set to strlen(str).
1814 If str is 0 a null string is created. If str is "", an empty string is
1816 created.
1817 See also isNull() and isEmpty().
1819
1821 Ensures that at least newLen characters are allocated to the string,
1822 and sets the length of the string to newLen. Any new space allocated
1823 contains arbitrary data.
1824 See also reserve() and truncate().
1826
1828 Sets the string to the printed value of n in base base and returns a
1829 reference to the string. The returned string is in "C" locale.
1830 The base is 10 by default and must be between 2 and 36.
1832 QString string;
1834 string = string.setNum( 1234 ); // string == "1234"
1835
1837 This is an overloaded member function, provided for convenience. It
1838 behaves essentially like the above function.
1839 Sets the string to the printed value of n in base base and returns a
1841 reference to the string.
1842 The base is 10 by default and must be between 2 and 36.
1844
1846 This is an overloaded member function, provided for convenience. It
1847 behaves essentially like the above function.
1848 Sets the string to the printed value of n in base base and returns a
1850 reference to the string.
1851 The base is 10 by default and must be between 2 and 36.
1853
1855 This is an overloaded member function, provided for convenience. It
1856 behaves essentially like the above function.
1857 Sets the string to the printed value of n in base base and returns a
1859 reference to the string.
1860 The base is 10 by default and must be between 2 and 36.
1862
1864 This is an overloaded member function, provided for convenience. It
1865 behaves essentially like the above function.
1866 Sets the string to the printed value of n in base base and returns a
1868 reference to the string.
1869 The base is 10 by default and must be between 2 and 36.
1871
1873 This is an overloaded member function, provided for convenience. It
1874 behaves essentially like the above function.
1875
1877 This is an overloaded member function, provided for convenience. It
1878 behaves essentially like the above function.
1879
1881 This is an overloaded member function, provided for convenience. It
1882 behaves essentially like the above function.
1883 Sets the string to the printed value of n in base base and returns a
1885 reference to the string.
1886 The base is 10 by default and must be between 2 and 36.
1888
1890 This is an overloaded member function, provided for convenience. It
1891 behaves essentially like the above function.
1892 Sets the string to the printed value of n, formatted in format f with
1894 precision prec, and returns a reference to the string.
1895 The format f can be 'f', 'F', 'e', 'E', 'g' or 'G'. See arg() for an
1897 explanation of the formats.
1898
1900 This is an overloaded member function, provided for convenience. It
1901 behaves essentially like the above function.
1902 Sets the string to the printed value of n, formatted in format f with
1904 precision prec, and returns a reference to the string.
1905 The format f can be 'f', 'F', 'e', 'E', 'g' or 'G'. See arg() for an
1907 explanation of the formats.
1908
1910 Resizes the string to len characters and copies unicode into the
1911 string. If unicode is 0, nothing is copied, but the string is still
1912 resized to len. If len is zero, then the string becomes a null string.
1913 See also setLatin1() and isNull().
1915
1917 len )
1918 Resizes the string to len characters and copies unicode_as_ushorts into
1919 the string (on some X11 client platforms this will involve a byte-
1920 swapping pass).
1921 If unicode_as_ushorts is 0, nothing is copied, but the string is still
1923 resized to len. If len is zero, the string becomes a null string.
1924 See also setLatin1() and isNull().
1926
1928 Returns a string that has whitespace removed from the start and the
1929 end, and which has each sequence of internal whitespace replaced with a
1930 single space.
1931 Whitespace means any character for which QChar::isSpace() returns TRUE.
1933 This includes Unicode characters with decimal values 9 (TAB), 10 (LF),
1934 11 (VT), 12 (FF), 13 (CR), and 32 (Space).
1935 QString string = " lots\t of\nwhite space ";
1937 QString t = string.simplifyWhiteSpace();
1938 // t == "lots of white space"
1939 See also stripWhiteSpace().
1941
1943 Safely builds a formatted string from the format string cformat and an
1944 arbitrary list of arguments. The format string supports all the escape
1945 sequences of printf() in the standard C library.
1946 The %s escape sequence expects a utf8() encoded string. The format
1948 string cformat is expected to be in latin1. If you need a Unicode
1949 format string, use arg() instead. For typesafe string building, with
1950 full Unicode support, you can use QTextOStream like this:
1951 QString str;
1953 QString s = ...;
1954 int x = ...;
1955 QTextOStream( &str ) << s << " : " << x;
1956 For translations, especially if the strings contains more than one
1958 escape sequence, you should consider using the arg() function instead.
1959 This allows the order of the replacements to be controlled by the
1960 translator, and has Unicode support.
1961 The %lc escape sequence expects a unicode character of type ushort (as
1963 returned by QChar::unicode()). The %ls escape sequence expects a
1964 pointer to a zero-terminated array of unicode characters of type ushort
1965 (as returned by QString::ucs2()).
1966 See also arg().
1968 Examples:
1970
1972 Squeezes the string's capacity to the current content.
1973 See also capacity() and reserve().
1975
1977 Returns TRUE if the string starts with s; otherwise returns FALSE.
1978 If cs is TRUE (the default), the search is case sensitive; otherwise
1980 the search is case insensitive.
1981 QString str( "Bananas" );
1983 str.startsWith( "Ban" ); // returns TRUE
1984 str.startsWith( "Car" ); // returns FALSE
1985 See also endsWith().
1987
1989 Returns a string that has whitespace removed from the start and the
1990 end.
1991 Whitespace means any character for which QChar::isSpace() returns TRUE.
1993 This includes Unicode characters with decimal values 9 (TAB), 10 (LF),
1994 11 (VT), 12 (FF), 13 (CR) and 32 (Space), and may also include other
1995 Unicode characters.
1996 QString string = " white space ";
1998 QString s = string.stripWhiteSpace(); // s == "white space"
1999 See also simplifyWhiteSpace().
2001
2003 Returns the string converted to a double value.
2004 If ok is not 0: if a conversion error occurs, *ok is set to FALSE;
2006 otherwise *ok is set to TRUE.
2007 QString string( "1234.56" );
2009 double a = string.toDouble(); // a == 1234.56
2010 The string-to-number functions:
2012 toShort()
2014 toUShort()
2016 toInt()
2018 toUInt()
2020 toLong()
2022 toULong()
2024 toLongLong()
2026 toULongLong()
2028 toFloat()
2030 toDouble() can handle numbers represented in various locales. These
2032 representations may use different characters for the decimal point,
2033 thousands group sepearator and even individual digits. QString's
2034 functions try to interpret the string according to the current locale.
2035 The current locale is determined from the system at application startup
2036 and can be changed by calling QLocale::setDefault(). If the string
2037 cannot be interpreted according to the current locale, this function
2038 falls back on the "C" locale.
2039 bool ok;
2041 double d;
2042 QLocale::setDefault(QLocale::C);
2043 d = QString( "1234,56" ).toDouble(&ok); // ok == false
2044 d = QString( "1234.56" ).toDouble(&ok); // ok == true, d == 1234.56
2045 QLocale::setDefault(QLocale::German);
2046 d = QString( "1234,56" ).toDouble(&ok); // ok == true, d == 1234.56
2047 d = QString( "1234.56" ).toDouble(&ok); // ok == true, d == 1234.56
2048 Due to the ambiguity between the decimal point and thousands group
2050 separator in various locales, these functions do not handle thousands
2051 group separators. If you need to convert such numbers, use the
2052 corresponding function in QLocale.
2053 bool ok;
2055 QLocale::setDefault(QLocale::C);
2056 double d = QString( "1,234,567.89" ).toDouble(&ok); // ok == false
2057 Warning: If the string contains trailing whitespace this function will
2059 fail, and set *ok to false if ok is not 0. Leading whitespace is
2060 ignored.
2061 See also number(), QLocale::setDefault(), QLocale::toDouble(), and
2063 stripWhiteSpace().
2064
2066 Returns the string converted to a float value.
2067 Returns 0.0 if the conversion fails.
2069 If ok is not 0: if a conversion error occurs, *ok is set to FALSE;
2071 otherwise *ok is set to TRUE.
2072 For information on how string-to-number functions in QString handle
2074 localized input, see toDouble().
2075 Warning: If the string contains trailing whitespace this function will
2077 fail, settings *ok to false if ok is not 0. Leading whitespace is
2078 ignored.
2079 See also number().
2081
2083 Returns the string converted to an int using base base, which is 10 by
2084 default and must be between 2 and 36 or 0. If base is 0, the base is
2085 determined automatically using the following rules:
2086 If the string begins with "0x", it is assumed to be hexadecimal;
2088 If it begins with "0", it is assumed to be octal;
2090 Otherwise it is assumed to be decimal.
2092 Returns 0 if the conversion fails.
2094 If ok is not 0: if a conversion error occurs, *ok is set to FALSE;
2096 otherwise *ok is set to TRUE.
2097 QString str( "FF" );
2099 bool ok;
2100 int hex = str.toInt( &ok, 16 ); // hex == 255, ok == TRUE
2101 int dec = str.toInt( &ok, 10 ); // dec == 0, ok == FALSE
2102 Leading and trailing whitespace is ignored by this function.
2104 For information on how string-to-number functions in QString handle
2106 localized input, see toDouble().
2107 See also number().
2109
2111 Returns the string converted to a long using base base, which is 10 by
2112 default and must be between 2 and 36 or 0. If base is 0, the base is
2113 determined automatically using the following rules:
2114 If the string begins with "0x", it is assumed to be hexadecimal;
2116 If it begins with "0", it is assumed to be octal;
2118 Otherwise it is assumed to be decimal.
2120 Returns 0 if the conversion fails.
2122 If ok is not 0: if a conversion error occurs, *ok is set to FALSE;
2124 otherwise *ok is set to TRUE.
2125 Leading and trailing whitespace is ignored by this function.
2127 For information on how string-to-number functions in QString handle
2129 localized input, see toDouble().
2130 See also number().
2132
2134 Returns the string converted to a long long using base base, which is
2135 10 by default and must be between 2 and 36 or 0. If base is 0, the base
2136 is determined automatically using the following rules:
2137 If the string begins with "0x", it is assumed to be hexadecimal;
2139 If it begins with "0", it is assumed to be octal;
2141 Otherwise it is assumed to be decimal.
2143 Returns 0 if the conversion fails.
2145 If ok is not 0: if a conversion error occurs, *ok is set to FALSE;
2147 otherwise *ok is set to TRUE.
2148 Leading and trailing whitespace is ignored by this function.
2150 For information on how string-to-number functions in QString handle
2152 localized input, see toDouble().
2153 See also number().
2155
2157 Returns the string converted to a short using base base, which is 10 by
2158 default and must be between 2 and 36 or 0. If base is 0, the base is
2159 determined automatically using the following rules:
2160 If the string begins with "0x", it is assumed to be hexadecimal;
2162 If it begins with "0", it is assumed to be octal;
2164 Otherwise it is assumed to be decimal.
2166 Returns 0 if the conversion fails.
2168 If ok is not 0: if a conversion error occurs, *ok is set to FALSE;
2170 otherwise *ok is set to TRUE.
2171 Leading and trailing whitespace is ignored by this function.
2173 For information on how string-to-number functions in QString handle
2175 localized input, see toDouble().
2176 See also number().
2178
2180 Returns the string converted to an unsigned int using base base, which
2181 is 10 by default and must be between 2 and 36 or 0. If base is 0, the
2182 base is determined automatically using the following rules:
2183 If the string begins with "0x", it is assumed to be hexadecimal;
2185 If it begins with "0", it is assumed to be octal;
2187 Otherwise it is assumed to be decimal.
2189 Returns 0 if the conversion fails.
2191 If ok is not 0: if a conversion error occurs, *ok is set to FALSE;
2193 otherwise *ok is set to TRUE.
2194 Leading and trailing whitespace is ignored by this function.
2196 For information on how string-to-number functions in QString handle
2198 localized input, see toDouble().
2199 See also number().
2201
2203 Returns the string converted to an unsigned long using base base, which
2204 is 10 by default and must be between 2 and 36 or 0. If base is 0, the
2205 base is determined automatically using the following rules:
2206 If the string begins with "0x", it is assumed to be hexadecimal;
2208 If it begins with "0", it is assumed to be octal;
2210 Otherwise it is assumed to be decimal.
2212 Returns 0 if the conversion fails.
2214 If ok is not 0: if a conversion error occurs, *ok is set to FALSE;
2216 otherwise *ok is set to TRUE.
2217 Leading and trailing whitespace is ignored by this function.
2219 For information on how string-to-number functions in QString handle
2221 localized input, see toDouble().
2222 See also number().
2224
2226 Returns the string converted to an unsigned long long using base base,
2227 which is 10 by default and must be between 2 and 36 or 0. If base is 0,
2228 the base is determined automatically using the following rules:
2229 If the string begins with "0x", it is assumed to be hexadecimal;
2231 If it begins with "0", it is assumed to be octal;
2233 Otherwise it is assumed to be decimal.
2235 Returns 0 if the conversion fails.
2237 If ok is not 0: if a conversion error occurs, *ok is set to FALSE;
2239 otherwise *ok is set to TRUE.
2240 Leading and trailing whitespace is ignored by this function.
2242 For information on how string-to-number functions in QString handle
2244 localized input, see toDouble().
2245 See also number().
2247
2249 Returns the string converted to an unsigned short using base base,
2250 which is 10 by default and must be between 2 and 36 or 0. If base is 0,
2251 the base is determined automatically using the following rules:
2252 If the string begins with "0x", it is assumed to be hexadecimal;
2254 If it begins with "0", it is assumed to be octal;
2256 Otherwise it is assumed to be decimal.
2258 Returns 0 if the conversion fails.
2260 If ok is not 0: if a conversion error occurs, *ok is set to FALSE;
2262 otherwise *ok is set to TRUE.
2263 Leading and trailing whitespace is ignored by this function.
2265 For information on how string-to-number functions in QString handle
2267 localized input, see toDouble().
2268 See also number().
2270
2272 If newLen is less than the length of the string, then the string is
2273 truncated at position newLen. Otherwise nothing happens.
2274 QString s = "truncate me";
2276 s.truncate( 5 ); // s == "trunc"
2277 See also setLength().
2279 Example: network/mail/smtp.cpp.
2281
2283 Returns the QString as a zero terminated array of unsigned shorts if
2284 the string is not null; otherwise returns zero.
2285 The result remains valid so long as one unmodified copy of the source
2287 string exists.
2288 Example: dotnet/wrapper/lib/tools.cpp.
2290
2292 Returns the Unicode representation of the string. The result remains
2293 valid until the string is modified.
2294
2296 Returns an uppercase copy of the string.
2297 QString string( "TeXt" );
2299 str = string.upper(); // t == "TEXT"
2300 See also lower().
2302 Examples:
2304
2306 Returns the string encoded in UTF-8 format.
2307 See QTextCodec for more diverse coding/decoding of Unicode strings.
2309 See also fromUtf8(), ascii(), latin1(), and local8Bit().
2311 Example: network/archivesearch/archivedialog.ui.h.
2313
2316 Returns TRUE if s1 is not equal to s2; otherwise returns FALSE. Note
2317 that a null string is not equal to a not-null empty string.
2318 Equivalent to compare(s1, s2) != 0.
2320 See also isNull() and isEmpty().
2322
2324 This is an overloaded member function, provided for convenience. It
2325 behaves essentially like the above function.
2326 Returns TRUE if s1 is not equal to s2; otherwise returns FALSE. Note
2328 that a null string is not equal to a not-null empty string.
2329 Equivalent to compare(s1, s2) != 0.
2331 See also isNull() and isEmpty().
2333
2335 This is an overloaded member function, provided for convenience. It
2336 behaves essentially like the above function.
2337 Returns TRUE if s1 is not equal to s2; otherwise returns FALSE. Note
2339 that a null string is not equal to a not-null empty string.
2340 Equivalent to compare(s1, s2) != 0.
2342 See also isNull() and isEmpty().
2344
2346 Returns a string which is the result of concatenating the string s1 and
2347 the string s2.
2348 Equivalent to s1.append(s2).
2350
2352 This is an overloaded member function, provided for convenience. It
2353 behaves essentially like the above function.
2354 Returns a string which is the result of concatenating the string s1 and
2356 character s2.
2357 Equivalent to s1.append(s2).
2359
2361 This is an overloaded member function, provided for convenience. It
2362 behaves essentially like the above function.
2363 Returns a string which is the result of concatenating the character s1
2365 and string s2.
2366
2368 This is an overloaded member function, provided for convenience. It
2369 behaves essentially like the above function.
2370 Returns a string which is the result of concatenating the string s and
2372 character c.
2373 Equivalent to s.append(c).
2375
2377 This is an overloaded member function, provided for convenience. It
2378 behaves essentially like the above function.
2379 Returns a string which is the result of concatenating the character c
2381 and string s.
2382 Equivalent to s.prepend(c).
2384
2386 Returns TRUE if s1 is lexically less than s2; otherwise returns FALSE.
2387 The comparison is case sensitive.
2388 Equivalent to compare(s1, s2) < 0.
2390
2392 This is an overloaded member function, provided for convenience. It
2393 behaves essentially like the above function.
2394 Returns TRUE if s1 is lexically less than s2; otherwise returns FALSE.
2396 The comparison is case sensitive.
2397 Equivalent to compare(s1, s2) < 0.
2399
2401 Writes the string str to the stream s.
2402 See also Format of the QDataStream operators
2404
2406 Returns TRUE if s1 is lexically less than or equal to s2; otherwise
2407 returns FALSE. The comparison is case sensitive. Note that a null
2408 string is not equal to a not-null empty string.
2409 Equivalent to compare(s1,s2) <= 0.
2411 See also isNull() and isEmpty().
2413
2415 This is an overloaded member function, provided for convenience. It
2416 behaves essentially like the above function.
2417 Returns TRUE if s1 is lexically less than or equal to s2; otherwise
2419 returns FALSE. The comparison is case sensitive. Note that a null
2420 string is not equal to a not-null empty string.
2421 Equivalent to compare(s1, s2) <= 0.
2423 See also isNull() and isEmpty().
2425
2427 Returns TRUE if s1 is equal to s2; otherwise returns FALSE. Note that a
2428 null string is not equal to a not-null empty string.
2429 Equivalent to compare(s1, s2) == 0.
2431 See also isNull() and isEmpty().
2433
2435 This is an overloaded member function, provided for convenience. It
2436 behaves essentially like the above function.
2437 Returns TRUE if s1 is equal to s2; otherwise returns FALSE. Note that a
2439 null string is not equal to a not-null empty string.
2440 Equivalent to compare(s1, s2) == 0.
2442 See also isNull() and isEmpty().
2444
2446 This is an overloaded member function, provided for convenience. It
2447 behaves essentially like the above function.
2448 Returns TRUE if s1 is equal to s2; otherwise returns FALSE. Note that a
2450 null string is not equal to a not-null empty string.
2451 Equivalent to compare(s1, s2) == 0.
2453 See also isNull() and isEmpty().
2455
2457 Returns TRUE if s1 is lexically greater than s2; otherwise returns
2458 FALSE. The comparison is case sensitive.
2459 Equivalent to compare(s1, s2) > 0.
2461
2463 This is an overloaded member function, provided for convenience. It
2464 behaves essentially like the above function.
2465 Returns TRUE if s1 is lexically greater than s2; otherwise returns
2467 FALSE. The comparison is case sensitive.
2468 Equivalent to compare(s1, s2) > 0.
2470
2472 Returns TRUE if s1 is lexically greater than or equal to s2; otherwise
2473 returns FALSE. The comparison is case sensitive. Note that a null
2474 string is not equal to a not-null empty string.
2475 Equivalent to compare(s1, s2) >= 0.
2477 See also isNull() and isEmpty().
2479
2481 This is an overloaded member function, provided for convenience. It
2482 behaves essentially like the above function.
2483 Returns TRUE if s1 is lexically greater than or equal to s2; otherwise
2485 returns FALSE. The comparison is case sensitive. Note that a null
2486 string is not equal to a not-null empty string.
2487 Equivalent to compare(s1, s2) >= 0.
2489 See also isNull() and isEmpty().
2491
2493 Reads a string from the stream s into string str.
2494 See also Format of the QDataStream operators
2496
2499 http://doc.trolltech.com/qstring.html
2500 http://www.trolltech.com/faq/tech.html
2501
2503 Copyright 1992-2007 Trolltech ASA, http://www.trolltech.com. See the
2504 license file included in the distribution for a complete license
2505 statement.
2506
2508 Generated automatically from the source code.
2509
2511 If you find a bug in Qt, please report it as described in
2512 http://doc.trolltech.com/bughowto.html. Good bug reports help us to
2513 help you. Thank you.
2514 The definitive Qt documentation is provided in HTML format; it is
2516 located at $QTDIR/doc/html and can be read using Qt Assistant or with a
2517 web browser. This man page is provided as a convenience for those users
2518 who prefer man pages, although this format is not officially supported
2519 by Trolltech.
2520 If you find errors in this manual page, please report them to qt-
2522 bugs@trolltech.com. Please include the name of the manual page
2523 (qstring.3qt) and the Qt version (3.3.8).
2524Trolltech AS 2 February 2007 QString(3qt)