前节中我们了解了用构造器函数创建类,其实在ECMAScript 2015(也称为 ES6中已经引入了 JavaScript 类,JavaScript 类是 JavaScript 对象的模板。 class ClassName { constructor() { ... }} class Car { constructor(name, year) { this.name = name; this.year = year; }} function test(){ var myCar = new Car(); myCar.name = "Ford"; myCar.year = 2015;} function test1(){ var myCar = new Car("Ford",2015);} class Car { constructor(name, year) { this.name = name; this.year = year; } age() { let date = new Date(); //要使用变量,必须声明 return date.getFullYear() - this.year; }} function test2(){var myCar = new Car("Ford",2016);Console.log("My car is "+myCar.age()+" years old.")} class Car { constructor(name, year) { this.name = name; this.year = year; } age(x) { return x - this.year; }} function test3(){ var myCar = new Car("Ford",2016); Console.log("My car is "+myCar.age(2022)+" years old.")} 本节先分享到这里,祝大家每天都有进步。 |
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来自: yuxinrong > 《八、JS中的对象》