微信扫码支付成功后如何跳转？异步请求的查询订单接口要怎么写？

<script>
var t1;
var sum=0;
$(document).ready(function () {
    t1=setInterval("ajaxstatus()", 3000);
});         
function ajaxstatus() {
        sum++;
        if(sum>600){ window.clearInterval(t1);return false;}
        if(sum>180){
            m=sum % 10;
            if(m!=0){return false;}
        }
if ($("#out_trade_no").val() != 0) { 
$.ajax({ 
 url: "http://www.wojuhome.cn/app/_core/Extend/Vendor/wxpay/example/orderquery2.php", 
 type: "GET", 
 dataType:"json", 
 data: { out_trade_no:$("#out_trade_no").val() }, 
 beforeSend: function () {

            },
 success: function (data) { 
 if (data=="SUCCESS") { 
 window.location.href = "http://www.wojuhome.cn/app/_core/Extend/Vendor/wxpay/example/index.php"; //页面跳转 
 } 
 }, 
 error: function(XMLHttpRequest, textStatus, errorThrown) { 
 alert("请求订单状态出错");
 } 
 });
 } 
 }

http://blog.csdn.net/wanguo1987/article/details/47838463
https://segmentfault.com/q/1010000002934496