基本用法：

复制代码 代码如下:

var ajax = new AjaxObj(url);

ajax.addListener(200, function(r){

alert(r);

});

ajax.send();

也可以连续调用：

复制代码 代码如下:

var ajax = new AjaxObj(url).addListener(200, function(r){

alert(r);

}).send();

另外还支持自定义的POST或GET方式请求，以及监视不同的HTTP状态码，自己看代码琢磨吧 :)

完整代码：

复制代码 代码如下:

AjaxObj = function(url, method, content){

this.r = null;

this.url = url;

this.method = method;

this.content = content;

this.header = {};

this.header["Connection"] = "close";

this.header["Content-type"] = "application/x-www-form-urlencoded";

var self = this;

if(window.XMLHttpRequest){

this.r = new XMLHttpRequest();

}else if(window.ActiveXObject){

try {

this.r = new ActiveXObject("Msxml2.XMLHTTP");

} catch(e) {

try{

this.r = new ActiveXObject("Microsoft.XMLHTTP");

} catch(e) {

}

}

}

this.addListener = function(http_status, func){

if(!this.L)

this.L=[];

this.L[http_status] = func;

return this;

};

this.setHeader = function(name, value){

this.header[name] = value;

this.r.setRequestHeader(name, value);

return this;

};

this.send = function(){

if(this.method != "post" && this.method != "get")

this.method = "get";

this.r.open(this.method, this.url, true);

for(var h in this.header) {

this.r.setRequestHeader(h, this.header[h]);

}

this.r.send(this.content);

};

if(this.r) this.r.onreadystatechange = function(){

if(self.r.readyState == 4 && self.L[self.r.status] != null)

self.L[self.r.status](self.r.responseText);

};

};