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Question about php function preg_replace

I want to dynamically delete certain tags and their contents from an html file and think about how to use preg_replace, but I can not get the syntax correctly. Basically, this should, for example, do something like: Replace everything between (and including) "" with nothing.

Can someone help me with this please?

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5 answers

Easy dude.

To have a Ungreedy regexpr, use the U modifier. To make it multi-line, use the s-modifier. Knowing that to delete all paragraphs, use this template:

#<p[^>]*>(.*)?</p>#sU

Explain:

  • I use # separator so that there is no need to protect my \ characters (to have a more readable pattern)
  • <p[^>]*> : the part defining the starting paragraph (with a hypothetical style, for example)
  • (.*)? : All (in the "Insoluble" mode)
  • </p> : Obviously, the final paragraph

Hope that helps!

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I would suggest not trying to do this with regex. A safer approach is to use something like

Simple HTML DOM

Here is the link to the API link: Simple HTML DOM API Link

Another option is to use a DOMDocument

The idea here is to use a real HTML parser to parse the data, and then you can move / move around the tree and delete any elements / attributes / text that you need. This is a much cleaner approach than trying to use a regular expression to replace data in HTML.

 <?php $doc = new DOMDocument; $doc->loadHTMLFile('blah.html'); $content = $doc->documentElement; $table = $content->getElementsByTagName('table')->item(0); $delfirstTable = $content->removeChild($table); echo $doc->saveHTML(); ?>
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If you are trying to sanitize your data, it is often recommended to use a whitelist rather than a blacklist of certain terms and tags. It is easier to disinfect and prevent XSS attacks. There is a well-known library called HTML Purifier , which, although large and somewhat slow, has amazing results in terms of cleaning your data.

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If you do not know what is between the tags, Phill's answer will not work.

This will work if there are no other tags between them, and this is certainly a simpler case. You can replace the div with any tag you need, obviously.

 preg_replace('#<div>[^<]+</div>#','',$html);

If there may be other tags in the middle, this should work, but it may cause problems. You should probably go with the DOM solution above if so

 preg_replace('#<div>.+</div>#','',$html);

They are not tested.

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PSEUDO CODE

 function replaceMe($html_you_want_to_replace,$html_dom) { return preg_replace(/^$html_you_want_to_replace/, '', $html_dom); }

HTML Before

 <div>I'm Here</div><div>I'm next</div> <?php $html_dom = "<div>I'm Here</div><div>I'm next</div>"; $get_rid_of = "<div>I'm Here</div>"; replaceMe($get_rid_of); ?>

HTML After

 <div>I'm next</div>

I know this is a hack job

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