var ua = navigator.userAgent.toLowerCase();

            if(ua.match(/MicroMessenger/i)=="micromessenger") {

                 //return "weixin";

                 alert("微信")

            } else if (ua.match(/QQ/i) == "qq") {

                 //return "QQ";

                  alert("QQ")

            }else {

                 return false;   

                 alert("不是微信浏览器或手机qq浏览器");

            }