ajax 第十五节 AJAX-同源策略
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<h1>你好</h1>
<button>点我获取用户数据</button>
</body>
<script>
const btn = document.querySelector('button');
btn.onclick = function () {
const xhr = new XMLHttpRequest();
//同源可以省略,只写/data
xhr.open('GET', '/data');
xhr.send();
xhr.onreadystatechange = function () {
if (xhr.readyState == 4) {
if (xhr.status <= 200 && xhr.status < 300) {
console.log(xhr.response);
}
}
}
}
</script>
</html>
==================server.js====================
const { request, response } = require('express');
const express = require('express');
const app = express();
app.get('/home', (request, response) => {
response.sendFile(__dirname + '/index.html');
})
app.get('/data', (request, response) => {
const data = { name: 'xiaoming', age: '18' };
//setTimeout(() => {
response.send(JSON.stringify(data));
//}, 3000);
})
app.listen(8000, () => {
console.log('服务已经启动,8000端口监听中.......');
})