Node.js 中的服务器相关概念(常见的服务器任务)

const http = require('http');
// 创建一个 HTTP 服务器
const server = http.createServer((req, res) => {
  res.statusCode = 200; // 设置响应状态码
  res.setHeader('Content-Type', 'text/plain'); // 设置响应头
  res.end('Hello, Node.js Server!'); // 返回响应
});
// 启动服务器并监听端口
server.listen(3000, '127.0.0.1', () => {
  console.log('Server running at http://127.0.0.1:3000/');
});

const http = require('http');
const server = http.createServer((req, res) => {
  if (req.method === 'GET' && req.url === '/') {
    res.statusCode = 200;
    res.setHeader('Content-Type', 'text/plain');
    res.end('Welcome to the Home Page!');
  } else if (req.method === 'GET' && req.url === '/about') {
    res.statusCode = 200;
    res.setHeader('Content-Type', 'text/plain');
    res.end('This is the About Page!');
  } else {
    res.statusCode = 404;
    res.setHeader('Content-Type', 'text/plain');
    res.end('Page Not Found');
  }
});
server.listen(3000, '127.0.0.1', () => {
  console.log('Server running at http://127.0.0.1:3000/');
});

const express = require('express');
const app = express();
// 定义路由
app.get('/', (req, res) => {
  res.send('Welcome to the Home Page!');
});
app.get('/about', (req, res) => {
  res.send('This is the About Page!');
});
// 启动服务器
app.listen(3000, () => {
  console.log('Server running at http://127.0.0.1:3000/');
});

const express = require('express');
const app = express();
// 使用路由参数
app.get('/user/:id', (req, res) => {
  const userId = req.params.id;
  res.send(`User ID: ${userId}`);
});
app.listen(3000, () => {
  console.log('Server running at http://127.0.0.1:3000/');
});

const express = require('express');
const app = express();
// 定义中间件
app.use((req, res, next) => {
  console.log('Request received:', req.method, req.url);
  next(); // 调用下一个中间件或路由处理函数
});
// 定义路由
app.get('/', (req, res) => {
  res.send('Hello from the Home Page!');
});
app.listen(3000, () => {
  console.log('Server running at http://127.0.0.1:3000/');
});

const express = require('express');
const app = express();
// 请求体解析中间件
app.use(express.json());
// 日志中间件
app.use((req, res, next) => {
  console.log('Request received:', req.method, req.url);
  next();
});
app.post('/', (req, res) => {
  console.log('Request body:', req.body);
  res.send('Data received');
});
app.listen(3000, () => {
  console.log('Server running at http://127.0.0.1:3000/');
});