利用原型设置AJAX时返回值的奇怪表现

Question

本帖最后由 generalxu 于 2010-06-10 15:24:20 编辑

Answer 1

可能是ajax异步请求的原因，还没等返回呢就接着执行下面的代码了

Answer 2

 s.ajaxrequest();
 alert(s.response)
你用下状态判断，你ff看下它执行了几次

Answer 3

js代码是单线程执行,你发送ajax后，有可能还没等到tmp.status==200呢，就执行了alert(s.response).
应该绑定个回调事件。<script type='text/javascript'>  var ajax=function (){};
ajax.prototype.xmlhttp=null;
ajax.prototype.url='';
//ajax.prototype.response=null;
ajax.prototype.seturl=function(url)
{
    this.url=url;
}
ajax.prototype.setaction=function(action)
{
    this.action=action;
}
ajax.prototype.setstr=function(str)
{
    this.str=str;    
}
ajax.prototype.callBack = {
success : function(o){}
   ,fail    : function(o){} 
}
ajax.prototype.ajaxrequest=function()
{
        if(window.ActiveXObject)
        {
            this.xmlhttp=new ActiveXObject('Microsoft.XMLHTTP');    
        }
        else if(window.XMLHttpRequest)
        {
            this.xmlhttp=new XMLHttpRequest();    
        }
        
        if(this.xmlhttp!=null)
        {
            var tmp = this.xmlhttp;
            var self  = this;
            this.xmlhttp.onreadystatechange=function ()
            {
                if(tmp.readyState==4)
                {
                    if(tmp.status==200)
                    {
                       // ajax.prototype.response=tmp.responseText;
                        self.callBack.success.apply(tmp,[tmp.responseText])
                    }
                    else
                    {
                     self.callBack.success.apply(tmp,[tmp.statusText])
                    }
                }
            }
            
            if(this.action=='get')
            {
                this.xmlhttp.open('GET',this.url,true);
                this.xmlhttp.send(null);
            }
            else if(this.action=='post')
            {
                this.xmlhttp.open('POST',this.url,true);
                this.xmlhttp.setRequestHeader('Content-type','application/x-www-form-urlencoded');
                this.xmlhttp.send(this.str);
            }
        }
        else
        {
            alert('Your browser does not support AJAX');    
        }
}
function click1()
{
alert(1);
    var s= new ajax;
    s.seturl('s1.php?'+Math.random());
   // s.setaction('alert');
    s.setstr(null);
    s.setaction('get');
    s.ajaxrequest();
    s.callBack = {
     success : function(text){
     alert(text);
     }
       ,fail    : function(text){
        alert("Error:"+text);
       }
    }
    s=null;
}
    </script>

Answer 4

<script type='text/javascript'>     var ajax=function (){};
    ajax.prototype.xmlhttp=null;
    ajax.prototype.url='';
    //ajax.prototype.response=null;
    ajax.prototype.seturl=function(url)
    {
        this.url=url;
    }
    ajax.prototype.setaction=function(action)
    {
        this.action=action;
    }
    ajax.prototype.setstr=function(str)
    {
        this.str=str;    
    }
    ajax.prototype.callBack = {
        success : function(o){}
       ,fail    : function(o){} 
    }
    ajax.prototype.ajaxrequest=function()
    {
            if(window.ActiveXObject)
            {
                this.xmlhttp=new ActiveXObject('Microsoft.XMLHTTP');    
            }
            else if(window.XMLHttpRequest)
            {
                this.xmlhttp=new XMLHttpRequest();    
            }
            
            if(this.xmlhttp!=null)
            {
                var tmp        = this.xmlhttp;
                var self     = this;
                this.xmlhttp.onreadystatechange=function ()
                {
                    if(tmp.readyState==4)
                    {
                        if(tmp.status==200)
                        {
                           // ajax.prototype.response=tmp.responseText;
                            self.callBack.success.apply(tmp,[tmp.responseText])
                        }
                        else
                        {
                            self.callBack.fail.apply(tmp,[tmp.statusText])
                        }
                    }
                }
                
                if(this.action=='get')
                {
                    this.xmlhttp.open('GET',this.url,true);
                    this.xmlhttp.send(null);
                }
                else if(this.action=='post')
                {
                    this.xmlhttp.open('POST',this.url,true);
                    this.xmlhttp.setRequestHeader('Content-type','application/x-www-form-urlencoded');
                    this.xmlhttp.send(this.str);
                }
            }
            else
            {
                alert('Your browser does not support AJAX');    
            }
    }
    function click1()
    {
        var s= new ajax;
        s.seturl('s1.php?'+Math.random());
       // s.setaction('alert');
        s.setstr(null);
        s.setaction('get');
        s.ajaxrequest();
        s.callBack = {
            success : function(text){
                alert(text);
            }
           ,fail    : function(text){
                   alert("Error:"+text);
           }
        }
        s=null;
    }
       </script>