Class

终于来到Class的章节了,Class是ES6所新增,在这之前都是使用Prototype去进行物件导向的方式,虽然Class本质上也还是Prototype也就是syntax sugar,但确实使撰写程式时方便许多

class Person{    constructor(name, age){        this.name = name,        this.age = age    }    SayHi(){        console.log(this.name)    }}class Student extends Person {    constructor(name, age, grade, email) {        super(name, age)         this.grade = grade;        this.email = email;    }    intro(){        console.log(`My name is ${this.name} grade is ${this.grade}`)    }}const Nick = new Student("Nick", 22, "9", "text@gmailcom")console.log(Nick)

可以看到Prototype继承了Person类别,所以Class还是语法糖并不是像其他OOP语言一样

Static

顾名思义就是不会改变的,举圆周率因为不会变,所以把pi设定成Static确保是正确的数值

class Circle{    static pi = 3.14    constructor(radius){         this.radius = radius    }    areaFN(){        return this.radius * this.radius * Circle.pi    }}const c = new Circle(10)console.log(c.areaFN()) //314