微信公眾號支付，報(bào)支付簽名驗(yàn)證失敗，微信的在線簽名驗(yàn)證是通過的。是前端出錯(cuò)還是后臺(tái)接口出錯(cuò)？

$.ajax({

type:"post",
url:url_path+"/pay/weixinprepaid.json",
data:dataArray2,
async:false,
dataType:"json",

success:function(data){
    //調(diào)用微信支付控件完成支付
    var param = data.resInfo;
    var timeStamp = param.timeStamp.toString();
    var prepayid = "prepay_id="+param.prepayid;
    var noncestr = param.noncestr;
    var sign = param.sign;
    var signType = "MD5";
    var appid = param.appid;
        WeixinJSBridge.invoke(
        'getBrandWCPayRequest', {
                "appId":appid,               //公眾號名稱，由商戶傳入     
                "timeStamp":timeStamp,       //時(shí)間戳，自1970年以來的秒數(shù)     
                "nonceStr":noncestr,         //隨機(jī)串     
                "package":prepayid,     
                "signType":signType,         //微信簽名方式：     
                "paySign":sign               //微信簽名 
        },
        function(res){
            if(res.err_msg == "get_brand_wcpay_request:ok" ) {
              window.location.
            }else{
                                                           
            }
        }
);       

},
error:function(xml){

console.log(xml)
}

});

這是我前端調(diào)起支付的代碼

msg:"成功"
resInfo:

appid:"wx3169069333bfc3a1"
noncestr:"2dg8tz56eggjs6h9b4ck186c723alvag"
package:"Sign=WXPay"
partnerid:"1499166342"
prepayid:"wx30090614962920174c62b2ff3662300490"
sign:"15F4E62938A8F852D264592F7634B56E"
timestamp:1527642375

stateCode:0

這是后臺(tái)接口返回的data