JS校验url地址

var Utils = { isUrl : function(str_url) {  var strRegex =  "^((https|http|ftp|rtsp|mms)://)?[a-z0-9A-Z]{3}\.[a-z0-9A-Z][a-z0-9A-Z]{0,61}?[a-z0-9A-Z]\.com|net|cn|cc (:s[0-9]{1-4})?/$";   var re = new RegExp(strRegex);  //re.test()  if (re.test(str_url)) {   return true;  } else {   return false;  } }};