本文實例講述了ES6 class的應用。分享給大家供大家參考，具體如下：
class
使用class進行類的實現應用
'use strict';// User 類class User { constructor(name,age) { this.name = name; this.age = age; } static getName() { return 'User'; } static getAge() { return this.age; } setName(name) { this.name = name; } setAge(age) { this.age = age; } get info() { return 'name:' + this.name + ' | age:' + this.age; }}// Manager 類class Manager extends User{ constructor(name,age,password){ super(name,age); this.password = this.password; } changePwd(pwd) { return this.password = pwd; } get info() { var info = super.info; // 使用super繼承父級 get return info + ' === new'; }}// typeof User: function typeof Manager: functionconsole.log('typeof User: ', typeof User, ' typeof Manager: ', typeof Manager); let manager = new Manager('Li', 22, '123456');manager.setAge(23);console.log(manager.info); // name:Li | age:23 === newconsole.log(User.prototype);console.log(Manager.prototype); 在class之前使用原型對象定義類的應用
// 構造函數function User(name,age) { this.name = name; this.age = age;}// 原型User.prototype = { getName:function(){ return 'User'; }, setName:function(name){ this.name = name; }, getAge:function(){ return this.age; }, setAge:function(age){ this.age = age; }}// 取值函數和存執函數Object.defineProperty(User.prototype,'info', { get() { return 'name:' + this.name + ' | age:' + this.age; }});var user = new User('Joh', 26);console.log(user); // User {name: "Joh", age: 26}// 子類function Manager(name, age, password) { User.call(this, name, age); this.password = password;}Manager.__proto__ = User; // 繼承靜態方法Manager.prototype = Object.create(User.prototype); // 繼承prototype原型方法Manager.prototype.changePwd = function (pwd) { this.password = pwd;};var manager = new Manager('Li', 22, '123456');manager.setAge(23);console.log(manager.info); // name:Li | age:23console.log(User.prototype); // 不變console.log(Manager.prototype); // {changePwd:function(){}, info:"name:undefined | age:undefined", __proto__:指向Manager.prototype}使用 class 定義的類不被提升，需按順序執行
正常：
let user = new class User { constructor(name) { this.name = name; }}('Joh');console.log(user); // User {name: "Joh"}錯誤：
var man = new Man(); // 此處報錯，使用class聲明的類不會被提升 Uncaught ReferenceError: Man is not definedclass Man { constructor(name){ this.name = name; }}
希望本文所述對大家JavaScript程序設計有所幫助。
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