AJAX CORS

HTML

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>CORS</title>
    <style>
        #result{
            width:200px;
            height:100px;
            border:solid 1px #90b;
        }
    </style>
</head>
<body>
    <button>发送请求</button>
    <div id="result"></div>
    <script>
        const btn = document.querySelector('button');

        btn.onclick = function(){
            //1. 创建对象
            const x = new XMLHttpRequest();
            //2. 初始化设置
            x.open("GET", "http://127.0.0.1:8000/cors-server");
            //3. 发送
            x.send();
            //4. 绑定事件
            x.onreadystatechange = function(){
                if(x.readyState === 4){
                    if(x.status >= 200 && x.status < 300){
                        //输出响应体
                        console.log(x.response);
                    }
                }
            }
        }
    </script>
</body>
</html>

JS

//1. 引入express
const express = require('express');

//2. 创建应用对象
const app = express();

//3. 创建路由规则
// request 是对请求报文的封装
// response 是对响应报文的封装
app.all('/cors-server', (request, response)=>{
    //设置响应头
    response.setHeader("Access-Control-Allow-Origin", "*");
    response.setHeader("Access-Control-Allow-Headers", '*');
    response.setHeader("Access-Control-Allow-Method", '*');
    // response.setHeader("Access-Control-Allow-Origin", "http://127.0.0.1:5500");
    response.send('hello CORS');
});

//4. 监听端口启动服务
app.listen(8000, () => {
    console.log("服务已经启动, 8000 端口监听中....");
});

posted on 2023-01-30 20:22 垂序葎草阅读(19) 评论(0) 编辑收藏举报