Ajax按需讀取數(shù)據(jù)生成下級菜單

script language="javascript">
var http_request=false;
function send_request(url){//初始化,指定處理函數(shù)，發(fā)送請求的函數(shù)
http_request=false;
//開始初始化XMLHttpRequest對象
if(window.XMLHttpRequest){//Mozilla瀏覽器
http_request=new XMLHttpRequest();
if(http_request.overrideMimeType){//設置MIME類型
http_request.overrideMimeType("text/html");
}
}
else if(window.ActiveXObject){//IE瀏覽器
try{
http_request=new ActiveXObject("Xsxml2.XMLHTTP");
http_request.setRequestHeader("Content-Type","text/xml");
http_request.setRequestHeader("Content-Type","gb2312");
}
catch(e){
try{
http_request=new ActiveXObject("Microsoft.XMLHTTP");
http_request.setRequestHeader("Content-Type","text/xml");
http_request.setRequestHeader("Content-Type","gb2312");
}
catch(e){
}
}
}
if(!http_request){//異常，創(chuàng)建對象實例失敗
window.alert("不能創(chuàng)建XMLHttpRequest對象實例");
return false;
}
http_request.onreadystatechange=processRequest;
//確定發(fā)送請求的方式和URL以及是否同步執(zhí)行下段代碼
http_request.open("GET",url,true);
http_request.send(null);
}
//處理返回信息的函數(shù)
function processRequest(){
if(http_request.readyState==4){//判斷對象狀態(tài)
if(http_request.status==200){//信息已經(jīng)成功返回，開始處理信息
document.getElementById(currentPos).innerHTML=http_request.responseText;
}
else{//頁面不正常
alert("您所請求的頁面有異常");
}
}
}
function showRoles(obj){
document.getElementById(obj).parentNode.style.display="";
document.getElementById(obj).innerHTML="正在讀取數(shù)據(jù)..."
currentPos=obj;
send_request("jilian_data.asp?playPos="+obj);
}
/script>

table width="200" border="0" cellspacing="0" cellpadding="0">
tr>
td height="20">
a href="javascript:void(0)" onclick="showRoles('pos_1')">經(jīng)理室
/a>
/td>
/tr>
tr style="display:none">
td height="20" id="pos_1">nbsp;/td>
/tr>
tr>
td height="20">
a href="javascript:void(0)" onclick="showRoles('pos_2')">開發(fā)部/a>
/td>
/tr>
tr style="display:none">
td id="pos_2" height="20">nbsp;/td>
/tr>
/td>
/table>

%@LANGUAGE="VBSCRIPT" CODEPAGE="936"%>
%
playPos=request("playPos")
if playPos="pos_1" then
Response.Write("nbsp;nbsp;jinglibr>nbsp;nbsp;副總經(jīng)理")
end if
if playPos="pos_2" then
Response.Write("nbsp;nbsp;總工程師br>nbsp;nbsp;軟件工程師")
end if
%>