TypeScript 中的静态方法和实例方法

您可以在 Mongoose 模型上定义实例方法和静态函数。通过一些额外的配置，您也可以在 TypeScript 中注册方法和静态方法。

方法

要在 TypeScript 中定义一个 实例方法，请创建一个表示实例方法的新接口。您需要将该接口作为第三个泛型参数传递给 Schema 构造函数，并作为第三个泛型参数传递给 Model，如下所示。

import { Model, Schema, model } from 'mongoose';

interface IUser {
  firstName: string;
  lastName: string;
}

// Put all user instance methods in this interface:
interface IUserMethods {
  fullName(): string;
}

// Create a new Model type that knows about IUserMethods...
type UserModel = Model<IUser, {}, IUserMethods>;

// And a schema that knows about IUserMethods
const schema = new Schema<IUser, UserModel, IUserMethods>({
  firstName: { type: String, required: true },
  lastName: { type: String, required: true }
});
schema.method('fullName', function fullName() {
  return this.firstName + ' ' + this.lastName;
});

const User = model<IUser, UserModel>('User', schema);

const user = new User({ firstName: 'Jean-Luc', lastName: 'Picard' });
const fullName: string = user.fullName(); // 'Jean-Luc Picard'

静态方法

Mongoose 模型 没有为 静态方法 提供明确的泛型参数。如果您的模型包含静态方法，我们建议您创建一个 扩展 Mongoose 的 Model 接口的接口，如下所示。

import { Model, Schema, model } from 'mongoose';

interface IUser {
  name: string;
}

interface UserModel extends Model<IUser> {
  myStaticMethod(): number;
}

const schema = new Schema<IUser, UserModel>({ name: String });
schema.static('myStaticMethod', function myStaticMethod() {
  return 42;
});

const User = model<IUser, UserModel>('User', schema);

const answer: number = User.myStaticMethod(); // 42

Mongoose 现在支持自动类型化的静态函数，因为现在它在模式选项中提供。静态函数可以定义如下

import { Schema, model } from 'mongoose';

const schema = new Schema(
  { name: String },
  {
    statics: {
      myStaticMethod() {
        return 42;
      }
    }
  }
);

const User = model('User', schema);

const answer = User.myStaticMethod(); // 42

方法和静态方法

以下是您如何定义同时包含方法和静态方法的模型。

import { Model, Schema, HydratedDocument, model } from 'mongoose';

interface IUser {
  firstName: string;
  lastName: string;
}

interface IUserMethods {
  fullName(): string;
}

interface UserModel extends Model<IUser, {}, IUserMethods> {
  createWithFullName(name: string): Promise<HydratedDocument<IUser, IUserMethods>>;
}

const schema = new Schema<IUser, UserModel, IUserMethods>({
  firstName: { type: String, required: true },
  lastName: { type: String, required: true }
});
schema.static('createWithFullName', function createWithFullName(name: string) {
  const [firstName, lastName] = name.split(' ');
  return this.create({ firstName, lastName });
});
schema.method('fullName', function fullName(): string {
  return this.firstName + ' ' + this.lastName;
});

const User = model<IUser, UserModel>('User', schema);

User.createWithFullName('Jean-Luc Picard').then(doc => {
  console.log(doc.firstName); // 'Jean-Luc'
  doc.fullName(); // 'Jean-Luc Picard'
});