PHP Regular expression to replace link url

Question

I need to add href=" before an http:// if this http:// doesn't follow href=" or src="

Following code partly works. Partly means it considers <a href=" only but not src="

$str= preg_replace( 
    "/(?<!a href=\")((http|ftp)+(s)?:\/\/[^<>\s]+)/i", 
    "<a href=\"\\0\"> target=\"blank\">\\0</a>", 
    $str
);

Thank you guys in advance for your reply.

You also do not want to replace the URL if it is part of an anchor element, e.g. <a href="http://example.com">http://example.com</a> — Gordon
– Gordon, Commented Oct 27, 2010 at 21:13
Or a link, or a meta, or part of a script, etc., etc., etc., rant, rant, rant, conclusion: use a parser. — Wrikken
– Wrikken, Commented Oct 27, 2010 at 23:04
possible duplicate of RegEx match open tags except XHTML self-contained tags — Paŭlo Ebermann
– Paŭlo Ebermann, Commented Sep 15, 2011 at 14:12

PiTheNumber · Accepted Answer · 2012-06-25 09:19:07Z

7

$str= preg_replace( 
    "/(?<!a href=\")(?<!src=\")((http|ftp)+(s)?:\/\/[^<>\s]+)/i", 
    "<a href=\"\\0\" target=\"blank\">\\0</a>", 
    $str
);

PiTheNumber

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answered Oct 27, 2010 at 20:02

chaos

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1 Comment

Would be lovely if this included any sort of description / comments. Code-only answers are hard enough, but RegEx is a whole 'nother monster!