Okay, putting aside the arguments that HTML is rarely well formed and that regexps aren't the answer when you can't guarantee the purity of your data etc (ie use HTML::Parser), an answer to your question is as follows: 
$_ = qq{<html><foo>4~<font color="#FF0000"><b>,</b></font><fush>
        5~
        <fish>#555555<>6~    <font #444444>};

print "$_\n";
my %colours = (m!(\d+)~\s*<\s*font\s+[^#]*(#[A-F0-9]{6})!igs);

print $colours{4};  # will print #FF0000

[download]

This code will handle (some cases where) '#' appears elsewhere and will ignore any case where the colour does not contain 6 hex digits. It's case insensitive, and allows spaces all over the place. I still hope that you have some idea of your expected data, as there are many cases that this can still break.

Hope it helps.

jarich

Update: mdillon pointed out a copy error. Was @colours, needed to be %colours.

In reply to Re: Using a Regex to parse into keys by jarich
in thread Using a Regex to parse into keys by Kage

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