// 引用expess框架 const express = require('express'); // 处理路径 const path = require('path'); const bodyParser = require('body-parser'); // 创建网站服务器 const app = express(); app.use(bodyParser.json()); app.get('/first', (req, res) => { res.send('hello geyao') }) app.get('/responsdate', (req, res) => { res.send({ "name": "geyao" }) }) app.post('/post', (req, res) => { res.send(req.body); }) app.get('/get', (req, res) => { res.send(req.query); }) app.post('/json', (req, res) => { res.send(req.body); }) app.get('/readystate', (req, res) => { res.send('hello'); }) app.get('/error', (req, res) => { res.status(400).send('not ok'); }) app.use(express.static(path.join(__dirname))); // 监听端口 app.listen(3000); console.log('网站服务器启动成功, 请访问localhost')
ajax6.html
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <title>Document</title> </head> <body> <button id="btn">发送ajax请求</button> <script> var xhr = new XMLHttpRequest(); xhr.open('get', 'http://localhost:3000/error'); xhr.onreadystatechange = function() { // if (xhr.readyState == 4) { //属性获取状态码 console.log(xhr.responseText); console.log(xhr.status); if (xhr.status == 400) { console.log('请求出错'); } else if (xhr.readyState == 404) { console.log('地址错误'); } } xhr.onerror = function() { console.log('网络中断，无法发送ajax请求') } } xhr.send(); </script> </body> </html>
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