xs/template/kxmobileno1/user/unifiedorder.phtml

<script src="//res2.wx.qq.com/open/js/jweixin-1.4.0.js"></script>
<script>
    wx.config({$config});
    wx.ready(function () {
        wx.chooseWXPay({$payconfig});
    });
    wx.error(function (res) {
        alert(res)
    });
</script>