Regular expression to match URL - Php function

Following regular expression (regEx) can be used to replace the urls in a string with the anchor tags with href attribute points to that url. RegEx: https?://([-\w\.]+)+(:\d+)?(/([\w/_\.]*(\?\S+)?)?)? // Automatically link URL's inside text. function matchURL($string){ return(preg_replace('@(https?://([-\w\.]+)+(:\d+)?(/([\w/_\.]*(\?\S+)?)?)?)@', '$1', $string )); }