yichael_fightingsports_single/Server/FS.js

// 实现一个文件系统读写数据库
const fs = require('fs');
const path = require('path');
var fileName='./DB.json';
const FS = {
    // 读数据
    read: function (key) {
        fs.readFile(fileName, (err, data) => {
            const json = data ? JSON.parse(data) : {}
            console.log(json[key])
        })
    },
    write: function (key, value = '') {

        if(!fs.existsSync(fileName)){
            //创建文件
            fs.writeFileSync(fileName,0);
        }

        fs.readFile(fileName, (err, data) => {
            const json = data ? JSON.parse(data) : {}
            json[key] = value
            fs.writeFile(fileName, JSON.stringify(json), err => {
                console.log('写入成功')
            } )
        })
    },

};
module.exports = FS;