1 function createXHR() {
2 if (typeof XMLHttpRequest != "undefined") {
3 return new XMLHttpRequest();
4 } else if (typeof ActiveXObject != "undefined") {
5 if (typeof arguments.callee.activeXString != "string") {
6 var versions = ["MSXML2.XMLHttp.6.0", "MSXML2.XMLHttp.3.0", "MSXML2.XMLHttp"];
7
8 for (var i = 0, len = versions.length; i < len; i++) {
9 try {
10 var xhr = new ActiveXObject(versions[i]);
11 arguments.callee.activeXString = versions[i];
12 return xhr;
13 } catch (ex) {
14 //omit
15 }
16 }
17 }
18 return new ActiveXObject(arguments.callee.activeXString);
19 } else {
20 throw new Error("no xhr object available.");
21 }
22 }
