It sounds like you could do this with a regular expression. 
use File::Slurp;

sub fix_file {
  my $html = read_file($_[0]);
  my $replacement = ...read in replacement string...
  if ($html = s{<div align="center">nothing</div>}
               {<div align="center">$replacement</div>})
               # use g modifier?
  {
    ...write file...
  }
}

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In reply to Re: Editing HTML files by pc88mxer
in thread Editing HTML files by spivey49

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


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