构造函数

class Person{
    constructor(name,age){
      this.name=name;
    this.age=age;
  }
  sayHi(){
      console.log(`hello,${this.name},今年我${this.age}了`)
  }
}

class类的写法等价于函数写法

function Person(name,age){
    this.name=name;
  this.age=age
}
Person.prototype.sayHi=function(){
          console.log(`hello,${this.name},今年我${this.age}了`)
}
var p = new Person('dong',18)

静态方法

class EventCenter {
  static fire() {
          return 'fire';
  }
  static on(){
          return 'on
    }
}

继承

class Person{
    constructor(name,age){
      this.name=name;
    this.age=age;
  }
  sayHi(){
      console.log(`hello,${this.name},今年我${this.age}了`)
  }
}
class Student extends Person{
    constructor(name,age,score){
      super(name,age);
    this.score = score;
  }
  myScore(){
      console.log(`hello,${this.name},我考了${this.score}分`)
  }
}