to find url in text and make them hyperlink

$text = preg_replace("
  #((http|https|ftp)://(\S*?\.\S*?))(\s|\;|\)|\]|\[|\{|\}|,|\"|'|:|\<|$|\.\s)#ie",
  "'<a href=\"$1\" target=\"_blank\">$3</a>$4'",
  $text);