1HTML::Filter(3) User Contributed Perl Documentation HTML::Filter(3)
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6 HTML::Filter - Filter HTML text through the parser
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9 This module is deprecated. The "HTML::Parser" now provides the
10 functionally of "HTML::Filter" much more efficiently with the "default"
11 handler.
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14 require HTML::Filter;
15 $p = HTML::Filter->new->parse_file("index.html");
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18 "HTML::Filter" is an HTML parser that by default prints the original
19 text of each HTML element (a slow version of cat(1) basically). The
20 callback methods may be overridden to modify the filtering for some
21 HTML elements and you can override output() method which is called to
22 print the HTML text.
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24 "HTML::Filter" is a subclass of "HTML::Parser". This means that the
25 document should be given to the parser by calling the $p->parse() or
26 $p->parse_file() methods.
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29 The first example is a filter that will remove all comments from an
30 HTML file. This is achieved by simply overriding the comment method to
31 do nothing.
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33 package CommentStripper;
34 require HTML::Filter;
35 @ISA=qw(HTML::Filter);
36 sub comment { } # ignore comments
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38 The second example shows a filter that will remove any <TABLE>s found
39 in the HTML file. We specialize the start() and end() methods to count
40 table tags and then make output not happen when inside a table.
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42 package TableStripper;
43 require HTML::Filter;
44 @ISA=qw(HTML::Filter);
45 sub start
46 {
47 my $self = shift;
48 $self->{table_seen}++ if $_[0] eq "table";
49 $self->SUPER::start(@_);
50 }
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52 sub end
53 {
54 my $self = shift;
55 $self->SUPER::end(@_);
56 $self->{table_seen}-- if $_[0] eq "table";
57 }
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59 sub output
60 {
61 my $self = shift;
62 unless ($self->{table_seen}) {
63 $self->SUPER::output(@_);
64 }
65 }
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67 If you want to collect the parsed text internally you might want to do
68 something like this:
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70 package FilterIntoString;
71 require HTML::Filter;
72 @ISA=qw(HTML::Filter);
73 sub output { push(@{$_[0]->{fhtml}}, $_[1]) }
74 sub filtered_html { join("", @{$_[0]->{fhtml}}) }
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77 HTML::Parser
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80 Copyright 1997-1999 Gisle Aas.
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82 This library is free software; you can redistribute it and/or modify it
83 under the same terms as Perl itself.
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87perl v5.30.1 2020-02-04 HTML::Filter(3)