創建不了XMLHTTP控件

最近在用AJax開發服務器程序，發現IE浏覽器不支持xmlhttprequest對象，而且找不到Microsoft.XMLHTTP控件。

問題出現了我們需要解決，解決方案如下：

1、運行下regsvr32 msXML3.dll；
2、用現成的框架來做AJax；
3、代碼優化：

if(window.ActiveXObject)
    {
        xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
    }
    else if(window.XMLHttpRequest)
    {
        xmlHttp = new XMLHttpRequest();
    }

    if(handle_s == null)
        handle_s = "bin/normal.py/db";
    this.XMLHttp.onreadystatechange = handle_l;
    this.XMLHttp.open("GET",handle_s,true);
    this.XMLHttp.send(null);

或判斷浏覽器

var agt = navigator.userAgent.toLowerCase();
var is_ie = (agt.indexOf("msIE") != -1);
var is_ie5 = (agt.indexOf("msIE 5") != -1);
var is_opera = (agt.indexOf("Opera") != -1);
var is_mac = (agt.indexOf("Mac") != -1);
var is_gecko = (agt.indexOf("gecko") != -1);
var is_safari = (agt.indexOf("safari") != -1);

function CreateXMLHttpReq(handler) {

var XMLhttp = null;
if (is_IE) {
// Guaranteed to be ie5 or IE6
var control = (is_IE5) ? "Microsoft.XMLHTTP" : "Msxml2.XMLHTTP";

try {
XMLhttp = new ActiveXObject(control);
XMLhttp.onreadystatechange = handler;
} catch (ex) {
// TODO: better help message
alert("You need to enable active scripting and activeX controls");
}

} else {

// Mozilla
xmlhttp = new XMLHttpRequest();
XMLhttp.onload = handler;
XMLhttp.onerror = handler;

}

return XMLhttp;
}

或者

<script language="Javascript">
    var http_request = false;
    function send_request(url) {//初始化、指定處理函數、發送請求的函數
        http_request = false;
        //開始初始化XMLHttpRequest對象
        if(window.XMLHttpRequest) { //Mozilla 浏覽器
            http_request = new XMLHttpRequest();
            if (http_request.overrideMimeType) {//設置MiME類別
                http_request.overrideMimeType('text/XML');
            }
        }
        else if (window.ActiveXObject) { // IE浏覽器
            try {
                http_request = new ActiveXObject("Msxml2.XMLHTTP");
} catch (e) {
                try {
                    http_request = new ActiveXObject("Microsoft.XMLHTTP");
                } catch (e) {}
            }
        }
        if (!http_request) { // 異常，創建對象實例失敗
            window.alert("不能創建XMLHttpRequest對象實例.");
            return false;
        }
        http_request.onreadystatechange = processRequest;
        // 確定發送請求的方式和URL以及是否同步執行下段代碼
        http_request.open("GET", url, true);
        http_request.send(null);
    }
    // 處理返回信息的函數
    function processRequest() {
        if (http_request.readyState == 4) { // 判斷對象狀態
            if (http_request.status == 200) { // 信息已經成功返回，開始處理信息
                var returnObj = http_request.responseXML;
                var xmlobj = http_request.responseXML;
                var employees = XMLobj.getElementsByTagName("employee");
                var feedbackStr = "";
                for(var i=0;i<employees.length;i++) { // 循環讀取employees.XML的內容
                    var employee = employees[i];
                    feedbackStr += "員工：" + employee.getAttribute("name");//取得標簽指定屬性
                    feedbackStr += " 職位：" + employee.getElementsByTagName("job")[0].firstChild.data;//取得指定標簽的最初數據
                    feedbackStr += " 工資：" + employee.getElementsByTagName("salary")[0].firstChild.data;
         &nbsp;          feedbackStr +=  "\r\n";
                }
                alert(feedbackStr);
            } else { //頁面不正常
                alert("您所請求的頁面有異常。");
            }
        }
    }
</script>