如何<a href>使用php</a>替换所有textlink并添加<a href>标签？</a>

Question

i want to add <a href=""> to all textlink which i missed add <a href=""> when i submit post.

Ex:

<a href"http://google.com">google.com</a> and https://paypal.com

And i just want to add <a href=""> for text https://paypal.com which i missed add <a href="">

Thanks!

Answer 1

The solution using preg_replace function and negative lookbehind assertion :

$str = '<a href="http://google.com">google.com</a> and https://paypal.com';
$result = preg_replace("/(?<![=\">])https?:\/\/([^\s]+)/", '<a href="$1">$1</a>', $str);

print_r($result);

The output(as source code):

<a href="http://google.com">google.com</a> and <a href="paypal.com">paypal.com</a>

(?<!=\\") - negative lookbehind assertion, ensures that matched URL is not preceded by attribute assignment ="