1XML::Handler::XMLWriterU(s3e)r Contributed Perl DocumentaXtMiLo:n:Handler::XMLWriter(3)
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6 XML::Handler::XMLWriter - a PerlSAX handler for writing readable XML
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9 use XML::Parser::PerlSAX;
10 use XML::Handler::XMLWriter;
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12 $my_handler = XML::Handler::XMLWriter->new( I<OPTIONS> );
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14 XML::Parser::PerlSAX->new->parse(Source => { SystemId => 'REC-xml-19980210.xml' },
15 Handler => $my_handler);
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18 "XML::Handler::XMLWriter" is a PerlSAX handler for writing readable XML
19 (in contrast to Canonical XML, for example). XML::Handler::XMLWriter
20 can be used with a parser to reformat XML, with XML::DOM or XML::Grove
21 to write out XML, or with other PerlSAX modules that generate events.
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23 "XML::Handler::XMLWriter" is intended to be used with PerlSAX event
24 generators and does not perform any checking itself (for example,
25 matching start and end element events). If you want to generate XML
26 directly from your Perl code, use the XML::Writer module. XML::Writer
27 has an easy to use interface and performs many checks to make sure that
28 the XML you generate is well-formed.
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30 "XML::Handler::XMLWriter" is a subclass of "XML::Handler::Subs".
31 "XML::Handler::XMLWriter" can be further subclassed to alter it's
32 behavior or to add element-specific handling. In the subclass, each
33 time an element starts, a method by that name prefixed with `s_' is
34 called with the element to be processed. Each time an element ends, a
35 method with that name prefixed with `e_' is called. Any special
36 characters in the element name are replaced by underscores. If there
37 isn't a start or end method for an element, the default action is to
38 write the start or end tag. Start and end methods can use the
39 `"print_start_element()"' and `"print_end_element()"' methods to print
40 start or end tags. Subclasses can call the `"print()"' method to write
41 additional output.
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43 Subclassing XML::Handler::XMLWriter in this way is similar to
44 XML::Parser's Stream style.
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46 XML::Handler::Subs maintains a stack of element names,
47 `"$self-"{Names}', and a stack of element nodes, `"$self-"{Nodes}>'
48 that can be used by subclasses. The current element is pushed on the
49 stacks before calling an element-name start method and popped off the
50 stacks after calling the element-name end method.
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52 See XML::Handler::Subs for additional methods.
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54 In addition to the standard PerlSAX handler methods (see PerlSAX for
55 descriptions), XML::Handler::XMLWriter supports the following methods:
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57 new( OPTIONS )
58 Creates and returns a new instance of XML::Handler::XMLWriter with
59 the given OPTIONS. Options may be changed at any time by modifying
60 them directly in the hash returned. OPTIONS can be a list of key,
61 value pairs or a hash. The following OPTIONS are supported:
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63 Output
64 An IO::Handle or one of it's subclasses (such as IO::File), if
65 this parameter is not present and the AsString option is not
66 used, the module will write to standard output.
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68 AsString
69 Return the generated XML as a string from the `"parse()"'
70 method of the PerlSAX event generator.
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72 Newlines
73 A true or false value; if this parameter is present and its
74 value is true, then the module will insert an extra newline
75 before the closing delimiter of start, end, and empty tags to
76 guarantee that the document does not end up as a single, long
77 line. If the paramter is not present, the module will not
78 insert the newlines.
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80 IsSGML
81 A true or false value; if this parameter is present and its
82 value is true, then the module will generate SGML rather than
83 XML.
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85 print_start_element($element)
86 Print a start tag for `$element'. This is the default action for
87 the PerlSAX `"start_element()"' handler, but subclasses may use
88 this if they define a start method for an element.
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90 print_end_element($element)
91 Prints an end tag for `$element'. This is the default action for
92 the PerlSAX `"end_element()"' handler, but subclasses may use this
93 if they define a start method for an element.
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95 print($output)
96 Write `$output' to Output and/or append it to the string to be
97 returned. Subclasses may use this to write additional output.
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100 • An Elements option that provides finer control over newlines than
101 the Newlines option, where you can choose before and after newline
102 for element start and end tags. Inspired by the Python XMLWriter.
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104 • Support Doctype and XML declarations.
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107 Ken MacLeod, ken@bitsko.slc.ut.us This module is partially derived from
108 XML::Writer by David Megginson.
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111 perl(1), PerlSAX.pod(3)
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115perl v5.34.0 2021-07-27 XML::Handler::XMLWriter(3)