TypeScript Classes All In One

// class Employee {
//   constructor(name: string) {
//     this.name = name;
//     // Property 'name' does not exist on type 'Employee'.ts(2339)
//   }
// }

class Employee {
  // name: string;
  name: string = '';
  // age?: number;
  age?: number = 0;
  constructor(name: string, age?: number) {
    this.name = name;
    if (age) {
      this.age = age;
    }
  }
  greet() {
    console.log(`employee name = ${this.name}`);
  }
  getAge() {
    console.log('age =', this.age);
  }
}

const em = new Employee('xgqfrms');
em.name;
em.greet();

em.age;
em.getAge();

class Manager extends Employee {
  private title: string;
  constructor(name: string, title: string) {
    super(name);
    this.title = title;
  }
  getTitle() {
    console.log('title =', this.title);
  }
}

const ma = new Manager('xgqfrms', 'CTO');
// ma.title;
// Property 'title' is private and only accessible within class 'Manager'.ts(2341)
ma.getTitle();

access modifier

访问修饰符: public / private / protected / static

class UFO {
  public name: string = '';
  private id?: number = 0;
  constructor(name: string, id?: number) {
    this.name = name;
    if (id) {
      this.id = id;
    }
  }
  protected getName() {
    console.log(`UFO name = ${this.name}`);
  }
  getId() {
    console.log('UFO id =', this.id);
  }
  getAll() {
    this.getName();
    this.getId();
  }
}


// const ufo = new UFO('ufo', 007);
/*

Octal literals are not allowed in strict mode.ts(1121)
Octal literals are not available when targeting ECMAScript 5 and higher. Use the syntax '0o7'.ts(1085)
*/

const ufo = new UFO('ufo', 7);
ufo.name;
ufo.getId();
// ufo.getName();
// Property 'getName' is protected and only accessible within class 'UFO' and its subclasses.ts(2445)
ufo.getAll();

const ufo_binary = new UFO('ufo', 0b111);
const ufo_octal = new UFO('ufo', 0o007);
const ufo_hex = new UFO('ufo', 0x007);

class SpaceShip extends UFO {
  private uid: string = '2048';
  constructor(name: string, id?: number) {
    super(name, id);
  }
  static log(value: any) {
    console.log('static value =', value);
  }
  getUid() {
    console.log('private uid =', this.uid);
  }
  // 改写 getAll
  getAll(): void {
    this.getName();
    this.getId();
    // this.getAll();
    this.getUid();
  }
}

const ss = new SpaceShip('ss', 2022);
ss.name;
// ss.getName();
// Property 'getName' is protected and only accessible within class 'UFO' and its subclasses.ts(2445)
ss.getId();
ss.getUid();
ss.getAll();

refs

https://www.typescriptlang.org/docs/handbook/2/classes.html

https://www.typescriptlang.org/docs/handbook/classes.html

?xgqfrms 2012-2020

www.cnblogs.com/xgqfrms 发布文章使用：只允许注册用户才可以访问！

原创文章，版权所有??xgqfrms, 禁止转载 ???，侵权必究??！