【前端】NodeJS：实战案例——记账本

文章目录

[1 lowdb数据库](#1 lowdb数据库)
[2 记账本案例](#2 记账本案例)

1 lowdb数据库

安装lowdb版本："^1.0.0"：npm install [email protected]。
基本用法：

javascript 复制代码

//导入 lowdb
const low = require('lowdb')
const FileSync = require('lowdb/adapters/FileSync')
const adapter = new FileSync('db.json');
//获取 db 对象
const db = low(adapter);

//初始化数据
db.defaults({ posts: [], user: {} }).write()

//写入数据
db.get('posts').push({id: 2, title: '今天天气还不错~~'}).write();
db.get('posts').unshift({id: 3, title: '今天天气还不错~~'}).write();
//获取单条数据
let res = db.get('posts').find({id: 1}).value();
console.log(res);

//获取数据
console.log(db.get('posts').value());

//删除数据
let res = db.get('posts').remove({id: 2}).write();
console.log(res);

//更新数据
db.get('posts').find({id: 1}).assign({title: '今天下雨啦!!!'}).write();

javascript 复制代码

/*
	db.json
*/
{
  "posts": [
    {
      "id": 1,
      "title": "今天下雨啦!!!"
    }
  ],
  "user": {}
}

2 记账本案例

index.js

javascript 复制代码

var express = require('express');
var router = express.Router();
//导入 lowdb
const low = require('lowdb')
const FileSync = require('lowdb/adapters/FileSync')
const adapter = new FileSync(__dirname + '/../data/db.json');
//获取 db 对象
const db = low(adapter);
//导入 shortid
const shortid = require('shortid');

//记账本的列表
router.get('/account', function(req, res, next) {
  	//获取所有的账单信息
  	let accounts = db.get('accounts').value();
  	res.render('list', {accounts: accounts});
});

//添加记录
router.get('/account/create', function(req, res, next) {
  	res.render('create'); //render可将.ejs文件的内容响应给浏览器
});

//新增记录
router.post('/account', (req, res) => {
  	//生成 id
  	let id = shortid.generate();
  	//写入文件
  	db.get('accounts').unshift({id:id, ...req.body}).write();
  	//成功提醒
  	res.render('success', {msg: '添加成功~~~', url: '/account'});
});

//删除记录
router.get('/account/:id', (req, res) => {
  	//获取 params 的 id 参数
  	let id = req.params.id;
  	//删除
  	db.get('accounts').remove({id:id}).write();
  	//提醒
  	res.render('success', {msg: '删除成功~~~', url: '/account'});
});

module.exports = router;

create.ejs

html 复制代码

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>添加记录</title>
    <link
      href="/css/bootstrap.css"
      rel="stylesheet"
    />
    <link href="/css/bootstrap-datepicker.css" rel="stylesheet">
  </head>
  <body>
    <div class="container">
      <div class="row">
        <div class="col-xs-12 col-lg-8 col-lg-offset-2">
          <h2>添加记录</h2>
          <hr />
          <form method="post" action="/account">
            <div class="form-group">
              <label for="item">事项</label>
              <input
                name="title"
                type="text"
                class="form-control"
                id="item"
              />
            </div>
            <div class="form-group">
              <label for="time">时间</label>
              <input
                name="time"
                type="text"
                class="form-control"
                id="time"
              />
            </div>
            <div class="form-group">
              <label for="type">类型</label>
              <select name="type" class="form-control" id="type">
                <option value="-1">支出</option>
                <option value="1">收入</option>
              </select>
            </div>
            <div class="form-group">
              <label for="account">金额</label>
              <input
                name="account"
                type="text"
                class="form-control"
                id="account"
              />
            </div>
            
            <div class="form-group">
              <label for="remarks">备注</label>
              <textarea name="remarks" class="form-control" id="remarks"></textarea>
            </div>
            <hr>
            <button type="submit" class="btn btn-primary btn-block">添加</button>
          </form>
        </div>
      </div>
    </div>
    <script src="/js/jquery.min.js"></script>
    <script src="/js/bootstrap.min.js"></script>
    <script src="/js/bootstrap-datepicker.min.js"></script>
    <script src="/js/bootstrap-datepicker.zh-CN.min.js"></script>
    <script src="/js/main.js"></script>
  </body>
</html>

list.ejs

html 复制代码

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <link
      href="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/3.3.7/css/bootstrap.css"
      rel="stylesheet"
    />
    <style>
      label {
        font-weight: normal;
      }
      .panel-body .glyphicon-remove{
        display: none;
      }
      .panel-body:hover .glyphicon-remove{
        display: inline-block
      }
    </style>
  </head>
  <body>
    <div class="container">
      <div class="row">
        <div class="col-xs-12 col-lg-8 col-lg-offset-2">
          <h2>记账本</h2>
          <hr />
          <div class="accounts">
            <% accounts.forEach(item => { %>
            <div class="panel <%= item.type==='-1' ? 'panel-danger' : 'panel-success'  %>">
              <div class="panel-heading"><%= item.time %></div>
              <div class="panel-body">
                <div class="col-xs-6"><%= item.title %></div>
                <div class="col-xs-2 text-center">
                  <span class="label <%= item.type==='-1' ? 'label-warning' : 'label-success'  %>"><%= item.type==='-1' ? '支出' : '收入'  %></span>
                </div>
                <div class="col-xs-2 text-right"><%= item.account %> 元</div>
                <div class="col-xs-2 text-right">
                  <a href="/account/<%= item.id %>">
                  <span
                    class="glyphicon glyphicon-remove"
                    aria-hidden="true"
                  ></span>
                </a>
                </div>
              </div>
            </div>
            <% }) %>
          </div>
        </div>
      </div>
    </div>
  </body>
</html>