完整程式碼，請洽: https://github.com/Zrn-code/Node-js-tutorial/tree/node-04

# 請求方的重要物件

server.js

	const http = require('http'); // 導入 http 模塊

	const server = http.createServer((req , res) => {
	console.log(req.url,req.method); // 輸出請求方當前的網址及連接方式
	});
	server.listen(3000,'localhost', () => {
	console.log(`listening for requests on post 3000`);
	});

終端機

	PS C:\Users\user\Documents\tuts\node>node server.js
	listening for requests on post 3000
	// 當用戶造訪 localhost:3000
	/ GET
	// 當用戶造訪 localhost:3000/about
	/about GET

# 回應方的重要物件

	const http = require('http');
	const server = http.createServer((req , res) => {
	res.setHeader('Content-Type','text/plain'); // 設定 Content-Type 為文字檔
	res.write('Hello, Zrn!!'); // 撰寫 Hello, Zrn!!
	res.end(); // 將撰寫結果回應出去
	});
	server.listen(3000,'localhost', () => {
	console.log(`listening for requests on post 3000`);
	});

	const http = require('http');
	const server = http.createServer((req , res) => {
	res.setHeader('Content-Type','text/html'); //// 設定 Content-Type 為 html 檔
	res.write('<p>hello, Zrn!!</p>');
	res.write('<p>hello, Zrn again!!</p>');
	res.end();
	});
	server.listen(3000,'localhost', () => {
	console.log(`listening for requests on post 3000`);
	});

使用之前學過的 fs 模組的讀取函式，就可以將回應的內容寫成一個檔案，一併的回應出來

	const http = require('http');
	const fs = require('fs');
	const server = http.createServer((req , res) => {
	res.setHeader('Content-Type','text/html');

	fs.readFile('./views/index.html',(err, data)=>{
	if(err){
	console.log(err);
	res.end();
	} else {
	res.end(data);
	}
	});
	});
	server.listen(3000,'localhost', () => {
	console.log(`listening for requests on post 3000`);
	});

使用 switch 判斷當前請求方的網址，回應出不同的 html 頁面

	const server = http.createServer((req , res) => {
	res.setHeader('Content-Type','text/html');

	let path = './views';
	switch(req.url){
	case '/':
	path += 'index.html';
	break;
	case '/about':
	path += 'about.html';
	break;
	default:
	path += '404.html';
	break;
	}
	fs.readFile(path,(err, data)=>{
	if(err){
	console.log(err);
	res.end();
	} else {
	res.end(data);
	}
	});
	});

	let path = './views';
	switch(req.url){
	case '/':
	path += 'index.html';
	res.statusCode = 200;
	break;
	case '/about':
	path += 'about.html';
	res.statusCode = 200;
	break;
	case '/about-me':
	res.statusCode = 301;
	res.setHeader('Location','/about');
	res.end();
	break;
	default:
	path += '404.html';
	res.statusCode = 404;
	break;
	}