Given an HTML::Element, some match text and a formatting tag this code runs through and wraps matching text in the given formatting tags.

For example:

use strict;
use warnings;
use HTML::TreeBuilder;

my $root = HTML::TreeBuilder->new ();

$root->parse_file (*DATA);

formatText ($root, 'bold', 'b');
formatText ($root, 'wrap selected text in formatting', 'i');

print $root->as_HTML();

__DATA__
<p>This test script demonstrates a way to run through the <em>text</em
+> in a chunk of
HTML and wrap selected text in formatting tags. </p>
<p>Note that the text to be formatted must not contain any tags in the
+ original
or the text will not match and that no checks are made for silly nesti
+ng of
formatting - re-formatting bold text won't make it double <i>bold</i> 
+but will double
the bold tags.</p>

[download]

Prints

<html><head></head><body><p>This test script demonstrates a way to run
+ through the <em>text</em> in a chunk of HTML and <i>wrap selected te
+xt in formatting</i> tags. <p>Note that the text to be formatted must
+ not contain any tags in the original or the text will not match and 
+that no checks are made for silly nesting of formatting - re-formatti
+ng <b>bold</b> text won't make it double <i><b>bold</b></i> but will 
+double the <b>bold</b> tags.</body></html>

[download]
sub formatText {
    my ($node, $target, $tag) = @_;
    my @children = $node->detach_content ();
    my @newChildren;
    
    for (@children) {
        if (ref) {
            formatText ($_, $target, $tag);
            push @newChildren, $_;
            next;
        }
        
        my @fragments = split /($target)/, $_;
        
        while (@fragments) {
            push @newChildren, shift @fragments;
            
            last if ! @fragments;
            my $element = HTML::Element->new ($tag);
            $element->push_content (shift @fragments);
            push @newChildren, $element;
        }
    }

    $node->push_content (@newChildren) if @newChildren;
}

[download]

In reply to Format key words in HTML text by GrandFather

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.