AJAX同步提交和异步提交方法

AJAX提交有同步提交和异步提交两种方式。后一种方式为提交后不等服务器有响应继续执行客户端代码。可以利用异步提交显示一些界面效果，比如显示一些文字，动画等。如下代码供大家参考。

//提交客户端DataStore数据
//url--目的URL
//data--要提交的DataStore 对象或XML字符串
//action--页面的Action代码
//isAsync-true: Async mode;false: sync mode
function Execute(url,action,data,method,isAsync){
 var acturl = url+"";
 var hrf =  document.createElement("<A href='"+url+"'>");//URL格式化
 var tg = "DataStore";
 document.appendChild(hrf);
 acturl= hrf.href;
 if(url == "#")
 {
     acturl = acturl.replace("#","");
  var pos = acturl.indexOf("?");
  if(pos>0)acturl = acturl.substr(0,pos);
 }
 if (acturl.indexOf("?") > 0)
  acturl = acturl + "&IsExec=True&RequestAction=" + action;
 else
  acturl = acturl + "?IsExec=True&RequestAction=" + action;
 
 var _data = "";
 var execdata = "";
 if(typeof(data) == "object")
  _data = data.ToString();
 else if(typeof(data) == "string")
  _data = data;
 if(!isBase64Encode)
 {
  execdata = _data.replace(//xB7/g,"%B7");//由于服务器端Request处理中点，解码时会变成问号
  execdata = escape(_data).replace(//+/g,"%2B")//由于服务器端Request处理"+"解码时会变成空格
 }
 else
 {
  tg = "DataStoreBase64";
  execdata = _Encode64(_data);
 }
 
 var resdata;
 if(!method)method = "post";
 if(method.toLowerCase() == "get"){
     if(typeof(isAsync) == "undefined" || isAsync == false)
      resdata = GetRequest(acturl + "&" + tg + "=" + execdata,isAsync);
     else
         GetRequest(acturl + "&" + tg + "=" + execdata,isAsync);
 }
 else if(method.toLowerCase() == "post"){
     if(typeof(isAsync) == "undefined" || isAsync == false)
      resdata = PostRequest(acturl,tg + "=" + execdata,isAsync);
  else
      PostRequest(acturl,tg + "=" + execdata,isAsync);  
    }
 if(typeof(isAsync) == "undefined" || isAsync == false)
        return new ExecResult(resdata,acturl,action,_data,method);
}

var xmlhttp = null;

function GetRequest(url,isAsync)
{
 xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
 if(typeof(isAsync) == "undefined" || isAsync == false){
     xmlhttp.Open("GET",url,false);
 }
 else{
     xmlhttp.Open("GET",url,true);
     xmlhttp.onreadystatechange = HandleStateChange;
 }
 xmlhttp.send();
    if(typeof(isAsync) == "undefined" || isAsync == false)
     return xmlhttp.responseText;
}

function PostRequest(url,data,isAsync)
{
 xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
 if(typeof(isAsync) == "undefined" || isAsync == false)
     xmlhttp.Open("POST",url,false);
 else{
     xmlhttp.Open("POST",url,true);
     xmlhttp.onreadystatechange = HandleStateChange;
 }
 xmlhttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
 xmlhttp.send(data);
 if(typeof(isAsync) == "undefined" || isAsync == false)
     return xmlhttp.responseText;
}

//Add by Max Yu 2006-11-18
function HandleStateChange(){
    if (xmlhttp.readyState == 4){
        if(xmlhttp.responseText.indexOf("<DataStore") != 0)
     {
         var win = window.open("about:blank","_Error");
      win.document.write(xmlhttp.responseText);
      return;
     }
        if (typeof(ResDataLoaded) == "function")ResponseDataLoaded = ResDataLoaded;
 
  if (ResponseDataLoaded != null)
      ResponseDataLoaded(new DataStore(xmlhttp.responseText));
    }
}