打字稿这个表达式是不可构造的。继承类结构错误

Question

我是 Typescript 的新手，我正在尝试在应用程序中个性化我的错误类。

我总共有四门课； Exception、GenericError、BaseService、CarService 两个主要和两个继承。 GenericError 扩展了 ExceptionClass 并且 CarService 扩展了 BaseService。我无法更改 GenericError 类的构造函数属性。我收到此错误；

这个表达式是不可构造的。

TS Snippet

我的类继承逻辑有什么问题？

// Exception.ts
class ExceptionClass extends Error {
  status: number;
  message: string;
  errors?: object;
  constructor(status: number, message: string, errors?: object) {
    super(message);
    this.status = status;
    this.message = message;
    this.errors = errors;
  }
}

// GenericError.ts
class GenericException extends ExceptionClass {
  constructor(message?: string) {
    super(400, message || 'Internal Error');
  }
}

// BaseService.ts
class BaseService {
  genericError: GenericException;

  constructor(message: string) {
    this.genericError = new GenericException();
  }
}

// CarService.ts
export default class CarService extends BaseService {
  constructor() {
        super('')
        console.log("CarService started!");
    }
  async checkCar() {
    return new Promise(async (resolve: any, reject: any) => {
      //** Imagine some business logic that fails */
      const passwordsNotMatchErr = new this.genericError('Fail Reason bla bla');
      return reject(passwordsNotMatchErr);
    })
  }
}

Answer 1

问题在于以下行：

const passwordsNotMatchErr = new this.genericError('Fail Reason bla bla');

您正在尝试创建已在类的构造函数中实例化的变量的实例。你正在尝试做类似const myString = new "I am a string and I can not be instantiated"

当你这样做时：

genericError: GenericException;

您正在做的是定义一个GenericExpection 类型的类变量（请记住，只能实例化类，不能实例化变量）。如果您想遵循您的架构，您可以执行以下操作：

  async checkCar() {
    return new Promise(async (resolve: any, reject: any) => {
      //** Imagine some business logic that fails */
      this.genericError = new GenericException('Fail Reason bla bla');
      return reject(this.genericError);
    })
  }

或

  async checkCar() {
    return new Promise(async (resolve: any, reject: any) => {
      //** Imagine some business logic that fails */
      const passwordsNotMatchErr = new GenericException('Fail Reason bla bla');
      return reject(passwordsNotMatchErr);
    })
  }