如何正确地在mongoose中使用ObjectId

const mongoose = require('mongoose');

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

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

const newUser = new User({
  _id: new mongoose.Types.ObjectId(),
  name: 'John',
  age: 25
});

newUser.save()
  .then(result => {
    console.log('User created:', result);
  })
  .catch(error => {
    console.error('Error creating user:', error);
  });

User.findById(userId)
  .then(user => {
    console.log('User found:', user);
  })
  .catch(error => {
    console.error('Error finding user:', error);
  });

User.findByIdAndUpdate(userId, { age: 30 })
  .then(updatedUser => {
    console.log('User updated:', updatedUser);
  })
  .catch(error => {
    console.error('Error updating user:', error);
  });

User.findByIdAndDelete(userId)
  .then(deletedUser => {
    console.log('User deleted:', deletedUser);
  })
  .catch(error => {
    console.error('Error deleting user:', error);
  });