Find links in text and replace to href with PHP

Here is the code to find the link in text and replace link as href,

function addlinks($text = ""){
 // The Regular Expression filter
 $reg_exUrl = "/(http|https|ftp|ftps)\:\/\/[a-zA-Z0-9\-\.]+\.[a-zA-Z]{2,3}(\/\S*)?/";
 // Check if there is a url in the text
 if(preg_match($reg_exUrl, $text, $url)) {
 // make the urls hyper links
 return  preg_replace($reg_exUrl, "<a href='{$url[0]}'>{$url[0]}</a> ", $text);
 } else {
 // if no urls in the text just return the text
 return $text;
 }
}

Example

Text : This is google website http://google.com

Output : This is google website http://google.com

Please comment with jQuery or javascript method to do the same.

Thanks in advance

Amjith