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<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>
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<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>
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