nodejs+express文件操作实现小型学生管理系统（增删改查）-纯享版

Posted 2022-02-18 勇敢*牛牛

实现文件数据更新功能

用来放置一些不希望被用户看见，但是需要被提交到服务端的数据

因为读取的文件信息，然后他的类型是字符串，切记

…………………………
	student.id = parseInt(student.id);
	var stu = students.find(function (item) 
	    return item.id === student.id
	)
…………………………      

app.js

var express = require('express');
var path = require('path');
var router = require(path.join(__dirname, './router'));
// 引包
var bodyParser = require('body-parser');

var server = express();

server.engine('html', require('express-art-template'));
server.set('views', path.join(__dirname, 'views'));

server.use('/node_modules/', express.static(path.join(__dirname, './node_modules/')));
server.use('/public/', express.static(path.join(__dirname, './public/')));


server.use(bodyParser.urlencoded( extended: false ))
    .use(bodyParser.json())


server.use(router);

server.listen(3000, function () 
    console.log('Run Server 3000……');
)

router.js

// 路由模块设计集合

var fs = require('fs');
var path = require('path');
var Student = require('./student');

var express = require('express');

var router = express.Router();

router.get('/students', function (req, res) 
  
    Student.find(function (err, students) 
        if (err) 
            return res.status(500).send('Server error.');
        
        res.render('index.html', 
            students: students
        );
    )
)
router.get('/students/new', function (req, res) 
    res.render('new.html');
)
router.post('/students/new', function (req, res) 
   
    var student = req.body;
    Student.save(student, function (err) 
        if (err) 
            return res.status(500).send('Server error.');
        
        res.redirect('/students');
    )

)
router.get('/students/edit', function (req, res) 
   
    Student.findId(parseInt(req.query.id), function (err, student) 
        if (err) 
            return res.status(500).send('Server error.');
        
        
        res.render('edit.html', 
            student: student
        )
    )

)
router.post('/students/edit', function (req, res) 

    Student.updataByid(req.body, function (err) 
        if (err) 
            return res.status(500).send('Server error.');
        
    )
    res.redirect('/students')
)
router.get('/students/delete', function (req, res) 
  
    Student.deleteByid(req.query.id, function (err) 
        if (err) 
            return res.status(500).send('Server error.');
        
        res.redirect('/students')
    )
)


module.exports = router;

student.js

var fs = require('fs');
var path = require('path');
var dbPath = './db.json';

exports.find = function (callback) 
    fs.readFile(path.join(__dirname, dbPath), 'utf8', function (err, data) 
        if (err) 
            return callback(err)
        
        callback(null, JSON.parse(data).student)
      
    )


exports.save = function (Nstudent, callback) 
    fs.readFile(path.join(__dirname, dbPath), 'utf8', function (err, data) 
        if (err) 
            return callback(err)
        
        var students = JSON.parse(data).student;

        Nstudent.id = students[students.length - 1].id + 1;

        students.push(Nstudent);

        var fileData = JSON.stringify(
            student: students
        )
        fs.writeFile(path.join(__dirname, dbPath), fileData, function (err) 
            if (err) 
                return callback(err)
            
            callback(null);

        );
    )


exports.updataByid = function (student, callback) 
    fs.readFile(path.join(__dirname, dbPath), 'utf8', function (err, data) 
        if (err) 
            return callback(err)
        
        var students = JSON.parse(data).student;
 
        student.id = parseInt(student.id);

        var stu = students.find(function (item) 
            return item.id === student.id
        )

        for (var key in student) 
            stu[key] = student[key];
        
        var fileData = JSON.stringify(
            student: students
        )
        fs.writeFile(path.join(__dirname, dbPath), fileData, function (err) 
            if (err) 
                return callback(err)
            
            callback(null);
        )

    )

exports.findId = function (id, callback) 
    fs.readFile(path.join(__dirname, dbPath), 'utf8', function (err, data) 
        if (err) 
            return callback(err)
        
        var students = JSON.parse(data).student;
        var ret = students.find(function (item) 
            return item.id === parseInt(id)
        )
        callback(null, ret);
    )

exports.deleteByid = function (id, callback) 
    fs.readFile(path.join(__dirname, dbPath), 'utf8', function (err, data) 
        if (err) 
            return callback(err)
        
        var students = JSON.parse(data).student;
      
        var deleteID = students.findIndex(function (item) 
            return item.id === parseInt(id);
        )
       
        students.splice(deleteID, 1);
       
        var fileData = JSON.stringify(
            student: students
        )
      
        fs.writeFile(path.join(__dirname, dbPath), fileData, function (err) 
            if (err) 
                return callback(err)
            
            callback(null);
        )

    )