Removing all html comments except internet explorer comments using regex and php

Question

I am new in regex but need a code that would remove all html comments () but not internet explorer comments like (). I have this code: 369

<?php
function stripTags($text, $tags)
{
  // replace the internet explorer comments tags so they do not get stripped  

  $text = preg_replace("<!--[if IE7] (.*?) <![endif]-->", "#?#", $text);

  // replace all the normal html comments
  $text =preg_replace('/<!--(.|\n)*?-->/g', '', $&text);


  // return internet explorer comments tags to their origial place

  $text = preg_replace("@#\?#@", "<!--[if IE7] (.*?) <![endif]-->", $text);

  return $text;
}
?>

Any help please.

http://stackoverflow.com/questions/1732348/regex-match-open-tags-except-xhtml-self-contained-tags/1732454#1732454 — jwueller, May 03 '11 at 11:47
When you convert the IE conditional comments, you don't store the original value anywhere. — alex, May 03 '11 at 11:48
Why do you need that? Comments do not have any influence on the page. — jwueller, May 03 '11 at 11:49
Possible duplicate: http://stackoverflow.com/questions/1013499/stripping-html-comments-with-php-but-leaving-conditionals — Kalessin, May 03 '11 at 11:57
I have seen the duplicate and its exactly what i needed. Thanks so much its great. — Juma Alphonce, May 04 '11 at 07:45

stema · Answer 1 · 2011-05-03T12:33:16.247

9

Why not just use a negative lookahead to ensure that the comment does not start with [if? that is easier to read and the comment can contain also [ and ].

<!--(?!\[if).*?-->

See here online

Update: A lookahead assertion is a non capturing(zero length) expression (like an achor \b that checks for a word boundary), that means it does not consum the characters, it checks if the expression is matching and if yes it continues right after the character before the expression. The negative one is checking that there isn't the expression following. I better link to a manual, here is the PerlReTut. Should be at that point no difference to php.

edited May 03 '11 at 12:33

answered May 03 '11 at 12:14

stema

90,351
20
107
135

please can you explain how how negative look ahead works? Thanks – AabinGunz May 03 '11 at 12:24
@Abhishek, I added some explanation and a link to my answer. – stema May 03 '11 at 12:34
The rubular online is wonderfull it makes regular expressions less thorny. Thanks so much for the link – Juma Alphonce May 04 '11 at 07:46
That is amazing - short and sweet - exactly what I was looking for. – mikevoermans Mar 28 '13 at 13:43

score 1 · Answer 2 · answered May 03 '11 at 12:07

1

If you know that no HTML comments on the page use the [ and ] characters, except for the if conditions, you can use:

preg_replace("//", "", $text);

answered May 03 '11 at 12:07

Craig Sefton

903
11
20

score 0 · Answer 3 · answered May 03 '11 at 11:54

0

try this
\

enter image description here

answered May 03 '11 at 11:54

AabinGunz

12,109
54
146
218

Removing all html comments except internet explorer comments using regex and php

3 Answers3

Linked