Match URL pattern in PHP using a regular expression

Question

I want to match a URL link in a wall post and replace this link with anchor tag. For this I use the regular expression below.

I would like the match four types of URL:

http://example.com
https://example.com
www.example.com
example.com

preg_replace('@(https?://([-\w\.]+)+(:\d+)?(/([\w/_\.]*(\?\S+)?)?)?)@',
             '$1', $subject);

This expression matches only first two types of URL.

If I use this expression for matching a URL pattern, '@(www?([-\w\.]+)+(:\d+)?(/([\w/_\.]*(\?\S+)?)?)?)@', it only matches the third type of URL pattern.

How can I match all four typeS of URL patternS with a single regular expression?

user_11982881 · Answer

This works great for me - including mailto check:

function LinkIt($text)
{
    $t = preg_replace("/(\b(?:(?:http(s)?|ftp):\/\/|(www\.)))([-a-züöäß0-9+&@#\/%?=~_|!:,.;]*[-a-z0-9+&@#\/%=~_|])/im", '$1$4', $text);
    return preg_replace("/([\w+\.\-]+@[\w+\-]+\.[a-zA-Z]{2,4})/im", strtolower('$1'), $t);
}

Match URL pattern in PHP using a regular expression

8 Answers