[Express] 安裝Express

[Express] 安裝Express

  • 創建資料夾 mkdir express_basic
  • 進入資料夾 cd express_basic
  • 初始化 pakcage.json 執行指令 npm init -y
  • 透過 npm 指令安裝 express:npm install express
  • 透過 npm 指令安裝 nodemon:npm install -g nodemon
  • 簡單範例
    • // Include express from node_modules
      const express = require('express')
      const app = express()
      
      // 在Express中,如果沒有定義 hostname,Express 就是預設用 loclhost
      const port = 3000
      
      // app.get - 設定路由
      // app.send - 設定伺服器回應的內容
      // app.listen - 啟動伺服器去監聽
      app.get('/', (req, res) => {
          res.send(`This is my first Express Web App started by nodemon !!!!!!!`)
      })
      
      app.get('/food', (req, res) => {
          res.send('My favorite food is ice cream')
      })
      
      app.get('/popular/languages', (req, res) => {
          res.send('JavaScript is a popular language')
      })
      
      app.get('/popular/languages/:language', (req, res) => {
          console.log('request params language is: ', req.params.language)
          res.send(`<h1>${req.params.language}is a popular language<h1>`)
      })
      
      // Start and listen the server
      app.listen(port, () => {
          console.log(`Express is running on http://localhost:${port}`)
      })
      
      

       

    • 透過 nodemon 執行 app.js 就可以啟動伺服器
    • end