导出Node.js中的Mongoose代码-将值传递给Mongoose方法的回调

npm install mongoose

const mongoose = require('mongoose');

mongoose.connect('mongodb://localhost/mydatabase', { useNewUrlParser: true, useUnifiedTopology: true })
  .then(() => {
    console.log('Connected to MongoDB');
    // 在连接成功后执行其他操作
  })
  .catch((error) => {
    console.error('Failed to connect to MongoDB', error);
  });

const userSchema = new mongoose.Schema({
  name: String,
  age: Number,
  email: String
});

const User = mongoose.model('User', userSchema);

const newUser = new User({
  name: 'John Doe',
  age: 25,
  email: 'john@example.com'
});

newUser.save()
  .then(() => {
    console.log('User created successfully');
  })
  .catch((error) => {
    console.error('Failed to create user', error);
  });

User.find()
  .then((users) => {
    console.log('Users:', users);
  })
  .catch((error) => {
    console.error('Failed to fetch users', error);
  });

User.updateOne({ name: 'John Doe' }, { age: 26 })
  .then(() => {
    console.log('User updated successfully');
  })
  .catch((error) => {
    console.error('Failed to update user', error);
  });

User.deleteOne({ name: 'John Doe' })
  .then(() => {
    console.log('User deleted successfully');
  })
  .catch((error) => {
    console.error('Failed to delete user', error);
  });