javascript 正则匹配url的域名、文件名字

/** 获取url的后缀名 */function urlRegEx(url){    var urlRgx=/http(s)?:\/\/([\w-]+\.)+[\w-]+(\/[\w- .\/?%&=]*)?(\/\w+)*.\w{3}$/;    if(urlRgx.test(url)){        var urlExtName = convert(url);    }    return urlExtName;}function convert(url){    url=url.replace(/(.*\/)*([^.]+).*/ig,"$2");    return url;}