帶有打字稿的貓鼬，來自貓鼬的錯誤“連接”

Question

當我啟動服務器時，出現此錯誤：

this.mongo.connect('mongodb://localhost:27017/tsnode', { ^ TypeError: 無法讀取未定義的屬性 'connect'

import express from 'express';
import mongoose from 'mongoose';
import cors from 'cors';

class App {
  public express: express.Application;

  public mongo: mongoose.Mongoose;

  constructor() {
    this.express = express();
    this.database();
    this.middlewares();
    this.routes();
  }

  private middlewares(): void {
    this.express.use(express.json());
    this.express.use(cors());
  }

  private database(): void {
    this.mongo.connect('mongodb://localhost:27017/tsnode', {
      useUnifiedTopology: true,
    });
  }

  private routes(): void {
    this.express.get('/', (req, res) => res.send('Hello World!'));
  }
}

export default new App().express;

Answer 1

您尚未啟動 mongo 變量，您應該在構造函數中進行。 喜歡：

  constructor() {
    this.express = express();
    this.mongo= mongoose;  // initialize mongo variable
    this.database();
    this.middlewares();
    this.routes();
  }