增删改查功能

首先，我们新建一个项目文件crudDemo，里面包含一个public文件夹，这个文件家里面放一些静态的资源会统一开放出去，views文件夹这里面放的是静态的页面，再加一个app.js入口文件，db.json文件我们用来存放数据，模拟数据库，然后，我们在命令行输入npm init -y初始化package.json文件，然后安装express插件，如下图

image.png

然后，我们在app.js文件中编写代码

**app.js**

const express = require('express');
const fs = require('fs');
const app = express();
app.engine('html', require('express-art-template'))
app.get('/', function(req, res) {
    fs.readFile('./db.json', function(error, data) {
        if(error) {
            return res.status(500).send('server error');
        }
        res.render('index.html', {
            section1: [
                {name: '帅哥', img: '/public/images/wall1.jpg'},
                {name: '美女', img: '/public/images/wall2.jpg'},
                {name: '明哥', img: '/public/images/wall4.jpg'}
            ],
            students: JSON.parse(data).students
        // 由于data是个字符串，我们需要先利用JSON.parse()方法把它转化成对象，然后在调用students属性
        })
    })
    
})
app.use('/public/', express.static('./public/'));
app.listen(8080, function() {
    console.log('running...')
})

**db.json**

{
    "students": [
        {"id": 1, "name": "张三", "sex": 0, "age": 18, "hobbies": "吃饭、睡觉、打豆豆" },
        {"id": 2, "name": "张三", "sex": 0, "age": 18, "hobbies": "吃饭、睡觉、打豆豆" },
        {"id": 3, "name": "张三", "sex": 0, "age": 18, "hobbies": "吃饭、睡觉、打豆豆" },
        {"id": 4, "name": "李四", "sex": 0, "age": 18, "hobbies": "吃饭、睡觉、打豆豆" },
        {"id": 5, "name": "张三", "sex": 0, "age": 18, "hobbies": "吃饭、睡觉、打豆豆" },
        {"id": 6, "name": "张三", "sex": 0, "age": 18, "hobbies": "吃饭、睡觉、打豆豆" },
        {"id": 7, "name": "张三", "sex": 0, "age": 18, "hobbies": "吃饭、睡觉、打豆豆" },
        {"id": 8, "name": "张三", "sex": 0, "age": 18, "hobbies": "吃饭、睡觉、打豆豆" }
    ]
}