IE8下ajax兼容问题

    function crossDomainAjax(url, successCallback) {

           // IE8 & 9 only Cross domain JSON GET request
           if ('XDomainRequest' in window && window.XDomainRequest !== null) {

               var xdr = new XDomainRequest(); // Use Microsoft XDR
               xdr.open('get', url);
               xdr.onload = function () {
                   var dom = new ActiveXObject('Microsoft.XMLDOM'),
                 JSON = $.parseJSON(xdr.responseText);

                   dom.async = false;

                   if (JSON == null || typeof (JSON) == 'undefined') {
                       JSON = $.parseJSON(data.firstChild.textContent);
                   }

                   successCallback(JSON); // internal function
               };

               xdr.onerror = function () {
                   _result = false;
               };

               xdr.send();
           }

           // IE7 and lower can't do cross domain
           else if (navigator.userAgent.indexOf('MSIE') != - &&
              parseInt(navigator.userAgent.match(/MSIE ([\d.]+)/)[], ) < ) {
               return false;
           }

           // Do normal jQuery AJAX for everything else
           else {
               $.ajax({
                   url: url,
                   cache: false,
                   dataType: 'json',
                   type: 'GET',
                   async: false, // must be set to false
                   success: function (data, success) {
                       successCallback(data);
                   }
               });
           }
       }

执行回调方法

           crossDomainAjax(url, function (data) {

               var newdata = data.Content;
               var str = "";
               for (var i = ; i < newdata.length; i++) {
                   str += '<li><a href="http://www.XXX.com/Crawler.aspx?purl=' + encodeURI(newdata[i].Producturl) + '" target="_blank"><div><img src="' + newdata[i].img + '"alt=""/></div><p>' + newdata[i].Name + '</p></a><p class="red">￥' + newdata[i].pric + '</p></li> ';
               }
               if (data.img != "" && data.img != null) {
                   $(".banner img").attr("src", data.img)
               } else {
                   $(".banner").hide();
               }
               document.title = data.title + '- Panli代购';
               callback(parseInt(data.Count));
               $(".content ul").html(str);
           });