自己写的封装好的简单的AJAX--javascript

  

//Ajax Function

 

var reqObj; //Creat Null Instence

 

//Run Ajax (string urladdress,bool IsAsy,string method,string parameters)

function DoRequest(url,isAsy,method,parStr) 

{

 

    reqObj = false;

 

    if (window.XMLHttpRequest) //compatible Mozilla, Safari,...

    {

       

        reqObj = new XMLHttpRequest();              //Creat XMLHttpRequest Instance

       

        if (reqObj.overrideMimeType)                //if Mime Type is false ,then set MimeType 'text/xml'

        {

            reqObj.overrideMimeType('text/xml');

        }

   

    }

   

    else if (window.ActiveXObject) //compatible IE

    {

   

        try

        {

            reqObj = new ActiveXObject("Msxml2.XMLHTTP"); //Creat XMLHttpRequest Instance

       }

        catch (e)

        {

            try

            {

                reqObj = new ActiveXObject("Microsoft.XMLHTTP"); //Creat XMLHttpRequest Instance

            }

            catch (e)

            {}

        }

   

    }

 

    //if reqObj is false,then alert warnning

    if (!reqObj)

    {

       

        alert('Giving up :( Cannot create an XMLHTTP instance');

        return false;

   

    }

   

   

    reqObj.onreadystatechange = GetRequest; //set onreadystatechange Function

   

    reqObj.open(method, url, isAsy);        //set open Function

   

    reqObj.setRequestHeader('Content-Type','application/x-www-form-urlencoded'); //set RequestHeader

   

    reqObj.send(parStr);   //do send and send parameters

 

}

 

 

//get Service Response information Function

function GetRequest()

{

 

    //judge readystate information

    if (reqObj.readyState == 4)

    {

        //judge status information

        if (reqObj.status == 200)

        {

            Ajax(reqObj);   //do custom Function at Ajax() and trans parameter reqObj

        }

        else

        {

            alert('There was a problem with the request.'+reqObj.status); //else alert warnning

        }

  

    }

 

}