var Ajax = {

post:function(){

xmlhttp = new XMLHttpRequest();

var len = arguments.length;

var url = arguments[0];

callback = arguments[len-1];

var str = '';

xmlhttp.open('POST', url, true);

xmlhttp.onreadystatechange=function()

{

if (xmlhttp.readyState==4 && xmlhttp.status==200)

{

callback(xmlhttp.responseText);

}

}

if (len = 3) {

data = arguments[1]

for(i in data){

str += i + "=" + data[i] +"&"

}

str = str.replace(/&$/gi,'')

}

if (len = 4) {

headers = arguments[2]

for(i in headers){

xmlhttp.setRequestHeader(i,headers[i])

}

}

xmlhttp.send(str);

}

}