jquery框架的ajax方法虽然好用，但是如果我们的项目需求简单，交互功能少，引入jquery会造成页面臃肿。
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Ems</title>
<style type="text/css">
#ems{
position: absolute;
left: 50%;
width: 400px;
height: auto;
margin-left: -200px;
background: lightGreen;
text-align: center;
min-height: 50px;
height: 500px;
overflow-y: scroll;
overflow-x: hidden;
}
#ems input{
height: 25px;
margin-top: 10px;
}
#list{
background: lightBlue;
}
#list li{
text-align: left;
}
</style>
</head>
<body>
<div id="ems">
<div>
<input type="text" id="code">
<input type="button" value="查询" id="btn">
</div>
<div id="list">
</div>
</div>
<script type="text/javascript">
function ajax(data) {
//我们封装的函数为了能实现可传入无限多个参数，在我们即将封装函数时，需要使用对象进行传参
//data = {data:"",dataType:"xml/json",type:"get/post",url:"",asyn:"true/false",success:function(){},filure:function(){}}
//
//data:{username:123,password:456} 发送的参数形式，用这种形式需要转换，所以用下面的字符串拼接的形式
//data = ‘username=123&password=456‘;
//第一步：创建xhr对象
var xhr = null;
if(window.XMLHttpRequest){
xhr = new XMLHttpRequest();
}else{
xhr = new ActiveXObject(‘Microsoft.XMLHTTP‘);
}
//第二步：准备发送前的一些配置参数
var type = data.type == ‘get‘?‘get‘:‘post‘;
var url =‘‘;
if(data.url){
url = data.url;
if(type == ‘get‘){
url += "?" + data.data + "&_t=" + new Date().getTime();
}
}
var flag = data.asyn == ‘true‘?‘true‘:‘false‘;
xhr.open(type,url,flag);
//第三步：执行发送的动作
if(type == ‘get‘){
xhr.send(null);
}else if(type == ‘post‘){
xhr.setRequestHeader("Content-Type","application/x-www-form-urlencoded");
xhr.send(data.data);
}
//第四步：指定回调函数
xhr.onreadystatechange = function () {
if(this.readyState == 4){
if(this.status == 200){
if(typeof data.success == ‘function‘){
var d = data.dataType == ‘xml‘?xhr.responseXML:xhr.responseText;
data.success(d);
}
}else{
if(typeof data.failure == ‘function‘) {
data.failure();
}
}
}
}
}
window.onload = function () {
var btn = document.getElementById(‘btn‘);
btn.onclick = function () {
var code = document.getElementById(‘code‘).value;
if(!code){
document.getElementById(‘list‘).innerHTML = "请输入查询单号";
return;
}
var param = {
data:‘code=‘+code,
url:‘07ems.php‘,
type:‘get‘,
dataType:‘json‘,
success:function(data){
var data = JSON.parse(data);
if(data.status == 0){
var list = data.data.info.context;
// console.log(list);
var tag = ‘‘;
for(var i=0;i<list.length;i++){
// console.log(list[i]);
var item = list[i];
var desc = item.desc;
var t = new Date();
t.setTime(item.time +‘000‘);
var str = t.getFullYear()+‘年‘+(t.getMonth()+1)+‘月‘+t.getDay()+‘日‘+(t.getHours()>12?‘ 下午‘:‘ 上午‘)+t.getHours()%12+‘:‘+t.getMinutes()+‘:‘+t.getSeconds();
tag += ‘<li><div>‘+str + ‘</div><div>‘ + desc+‘</div></li>‘
}
var ul = document.createElement(‘ul‘);
ul.innerHTML = tag;
document.getElementById(‘list‘).appendChild(ul);
}else{
var info = data.msg;
document.getElementById(‘list‘).innerHTML = info;
}
}
};
ajax(param);
}
}
</script>
</body>
</html>