第一次親密接觸Ajax

Ajax 架構
var http_request = false;
function send_request(url) {
 http_request = false;
 if(window.XMLHttpRequest) {
  http_request = new XMLHttpRequest();
  if (http_request.overrideMimeType) {
   http_request.overrideMimeType("text/xml");
  }
 }
 else if (window.ActiveXObject) {
  try {
   http_request = new ActiveXObject("Msxml2.XMLHTTP");
  } catch (e) {
   try {
    http_request = new ActiveXObject("Microsoft.XMLHTTP");
   } catch (e) {}
  }
 }
 if (!http_request) {
  window.alert("不能建立XMLHttpRequest 對象執行個體.");
  return false;
 }
 
 http_request.onreadystatechange = processFunction;
 
 http_request.open("GET", url, false);
 http_request.send(null);
}

function processFunction()
{
 if (http_request.readyState == 4) {
  if (http_request.status == 200) {
   var ResponseText = http_request.responseText;
   //var ResponseXml = http_request.responseXml;

   // 處理返回對象
  }
  else
  {
   alert("您所請求的頁面有異常。");
  }
 }
}

調用方法：
 send_request(url);
例如：
 send_request('process.asp?id=1&name=2');