mongoose创建模型对象

1. 目录结构

2. db.js 连接数据库，检测数据库状态

const mongoose = require('mongoose')
const PORT = 27017
const URL = 'localhost'
const DB = 'test'
//连接数据库
mongoose.connect(`mongodb://${URL}:${PORT}/${DB}`, {
  useNewUrlParser: true,
  useUnifiedTopology: true,
})
mongoose.set('useCreateIndex', true) //使用一个新的索引
let resultFlag = new Promise((resolve, reject) => {
  mongoose.connection.on('open', (err) => {
    if (err) {
      console.log('连接数据库失败', err)
      reject('failed')
    } else {
      console.log('数据库连接成功')
      resolve('success')
    }
  })
})
module.exports = resultFlag

3. stuModel.js 创建集合对象模型

const mongoose = require('mongoose')
//创建Schema(模型对象)
let Schema = mongoose.Schema
let studentSchema = new Schema({
  name: String,
  age: Number,
  sex: {
    type: String,
    default: '男',
  },
  stu_id: {
    type: Number,
    unique: true,
  },
  date: {
    type: Date,
    default: Date.now,
  },
  is_flag: {
    type: Boolean,
    default: true,
  },
})
//创建Model对象
let stuModel = mongoose.model('students', studentSchema)
module.exports = stuModel

4. app.js 引入数据库，引入对象模型！添加数据

//引入连接数据库的状态  resultFlag
let resultFlag = require('./db/db')
//引入对象模型
let stuModel = require('./SchemaModel/stuModel')

resultFlag
  .then((res) => {
    if (res == 'success') {
      stuModel.create({
        name: '王力宏',
        age: 26,
        sex: '男',
        stu_id: 16,
      })
    } else {
      console.log(res)
    }
  })
  .catch((err) => {
    console.log(err)
  })