<!DOCTYPE html>
<html lang="zh">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta http-equiv="X-UA-Compatible" content="ie=edge" />
<title>JavaScript AJAX原生写法 面试题</title>
</head>
<body>
<script type="text/javascript">
var Ajax = {
get: function(url, fn) {
//创建XMLHttpRequest对象
var xhr = new XMLHttpRequest();
//true表示异步
xhr.open('GET', url, true);
xhr.onreadystatechange = function() {
// readyState == 4说明请求已完成
if(xhr.readyState == 4 && xhr.status == 200 || xhr.status == 304) {
//responseText：从服务器获得数据
fn.call(this, xhr.responseText);
}
};
xhr.send();
},
post: function(url, data, fn) { //datat应为'a=a1&b=b1'这种字符串格式
var xhr = new XMLHttpRequest();
xhr.open("POST", url, true);
// 添加http头，发送信息至服务器时内容编码类型
xhr.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
xhr.onreadystatechange = function() {
if(xhr.readyState == 4 && (xhr.status == 200 || xhr.status == 304)) {
fn.call(this, xhr.responseText);
}
};
xhr.send(data);
}
}
</script>
</body>
</html>