如何利用微信内嵌H5网页解决JS倒计时失效的问题

<script type="text/javascript"><br> var timespan = '20160113'; //后台程序生成24小时时间差值，这里随便写写
  var timer;
  function UpdateTime() {
   if (timespan > 0) {
    var hour = Math.floor(timespan / (60 * 60));
    var minute = Math.floor((timespan - (hour * 60 * 60)) / 60);
    var second = (timespan - (hour * 60 * 60) - (minute * 60));
    var word = "支付剩余时间" + (hour<10?("0"+hour):hour) + "：" + (minute<10?("0"+minute):minute) + "：" + (second<10?("0"+second):second) + "，逾期订单将自动取消~";
    timespan--;
    jQuery(".tc").html("<i class='time'></i>" + word);
    timer = setTimeout("UpdateTime()", 1000);
   }
   else {
    $('.content').find('.w_op').hide();
    clearTimeout(timer);
    jQuery(".tc").html("<i class='time'></i>" + "订单过期，已自动取消~");
    window.location.href='@Url.Action("orderDetail", "Order", new { OrderNumber = Model.No })';; //订单过期，跳转到订单详情页
   }
  }
  jQuery(document).ready(function () {
   UpdateTime();
  });<br></script>

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