ajxa的封装

function json2url(json){

json.t = Math.random();

var arr = [];

for(var name in json){

arr.push(name+'='+json[name]);

}

return arr.join('&');

}

//url,data,type,time,fnSucc,fnFail

function ajax(json){

var json = json || {};

if(!json.url){

alert('没有地址！');

return;

}

json.data = json.data || {};

json.time = json.time || 1000;

json.type = json.type || 'GET';

//1.ajax对象  request:请求  response:响应

if(window.XMLHttpRequest){

var oAjax = new XMLHttpRequest();

}

else{

var oAjax = new ActiveXObject('Microsoft.XMLHTTP');

}

//2.建立连接

switch (json.type.toLowerCase()){

case 'post':

oAjax.open('POST',json.url,true);

oAjax.setRequestHeader('Content-Type','application/x-www-form-urlencoded');//设置一个请求头

oAjax.send(json2url(json.data));

break;

case 'get':

oAjax.open('GET',json.url+'?'+json2url(json.data),true);

//3.打开连接

oAjax.send();

break;

}

//4.接收

var timer = null;

oAjax.onreadystatechange = function(){

if(oAjax.readyState == 4){

//完成

if(oAjax.status >= 200 && oAjax.status<300 || oAjax.status == 304){

//成功

json.success && json.success(oAjax.responseText);

clearTimeout(timer);

}

else{

json.error && json.error(oAjax.status);

}

}

};

timer = setTimeout(function(){

alert('你的网速太慢了，别等了！！');

},json.time);

}