JS之正则表达式验证URL

function IsURL(str_url){     
    var strRegex = "^((https|http|ftp|rtsp|mms)?://)"      
                    + "?(([0-9a-zA-Z_!~*'().&=+$%-]+: )?[0-9a-zA-Z_!~*'().&=+$%-]+@)?" //ftp的user@     
                    + "(([0-9]{1,3}\.){3}[0-9]{1,3}" // IP形式的URL- 199.194.52.184     
                    + "|" // 允许IP和DOMAIN（域名）     
                    + "([0-9a-zA-Z_!~*'()-]+\.)*" // 域名- www.     
                    + "([0-9a-zA-Z][0-9a-zA-Z-]{0,61})?[0-9a-zA-Z]\." // 二级域名     
                    + "[a-zA-Z]{2,6})" // first level domain- .com or .museum     
                    + "(:[0-9]{1,4})?" // 端口- :80     
                    + "((/?)|"      
                    + "(/[0-9a-zA-Z_!~*'().;?:@&=+$,%#-]+)+/?)$";     
    var re=new RegExp(strRegex);     
    return re.test(str_url);     
}