html Ajax读取数据

 function InitXMLHTTP(){//初始化、指定处理函数、发送请求的函数
    var oXMLDoc;
    //开始初始化XMLHttpRequest对象
    if(window.XMLHttpRequest) { //Mozilla 浏览器
        oXMLDoc = new XMLHttpRequest();
        if (oXMLDoc.overrideMimeType) {//设置MiME类别
            oXMLDoc.overrideMimeType("text/xml");
        }
    }
    else if(window.ActiveXObject) { // IE浏览器
        try{
                oXMLDoc = new ActiveXObject("Msxml2.XMLHTTP");
            }catch (e){
        try{
                oXMLDoc = new ActiveXObject("Microsoft.XMLHTTP");
           } catch (e) {}
        }
    }
    if (!oXMLDoc) { // 异常，创建对象实例失败
        window.alert("不能创建XMLHttpRequest对象实例.");
        oXMLDoc = null;
    }
    return oXMLDoc;
}

function DispLink(_obj,_i,_Id)
{
    for(var i=0;i<topicCount;i++){
        document.getElementById("DivDispAnswer"+i).style.display = "none";
    }
    var oXMLDoc = InitXMLHTTP(); 
    if(oXMLDoc)
    {   
        sURL = "GetExpXML.asp?ItemId=" + _Id;
        oXMLDoc.open("POST",sURL,false);
        oXMLDoc.setRequestHeader("Content-Type", "text/xml");
        oXMLDoc.setRequestHeader("charset", "utf-8");
        oXMLDoc.send();
        var strResult = unescape(oXMLDoc.responseText);
        document.getElementById("DivDispAnswer"+_i).innerHTML = strResult;
        document.getElementById("DivDispAnswer"+_i).style.display = "block";
        if(document.getElementById("FS"+_i))
            document.getElementById("FS"+_i).focus();
        //_obj.innerHTML = "隐藏答案";
    }
}