<script> //1.使用new Object()方式定义 var person1 = new Object(); person1.name = '张三'; person1.age = 24; person1.gender = "male"; person1.introduceSelf = function () { alert("我的名字是:"+this.name+" "+"年龄:"+this.age+" 性别:"+this.gender); } alert(person.name) person.introduceSelf(); //使用字面量定义对象 var person2 = { name : "zhangsan", age : 25, gender : "female", introduceSelf : function () { alert("我的名字是:"+this.name+" "+"年龄:"+this.age+" 性别:"+this.gender); } } alert(person2.gender) person2.introduceSelf(); //创建对象的几种方式 //1. 工厂模式: 用函数封装以特定的接口创建对象的细节 function createPerson(name, age, gender) { var person = new Object(); person.age = age; person.name = name; person.gender = gender; person.introduceSelf= function () { alert("我的名字是:"+this.name+" "+"年龄:"+this.age+" 性别:"+this.gender); } return person; } var p1 = createPerson("lisi",18,"女"); var p2 = createPerson("貂蝉",16,"female"); p1.introduceSelf(); p2.introduceSelf(); //2. 构造函数模式 (系统自动帮我们创建了 var this = new Object(); 和return this;) //缺点:每个方法都要在每个实例上调用重新创建一遍 function Person(name, age, gender) { this.name = name; this.age = age; this.gender = gender; this.introduceSelf = function () { alert("我的名字是:"+this.name+" "+"年龄:"+this.age+" 性别:"+this.gender); } } var p3 = new Person("小乔",15,"妹纸"); var p4 = new Person("如花", 28, "汉子"); p3.introduceSelf(); p4.introduceSelf(); //3. 原型模式 , 让对象实例共享它所包含的属性和方法 function Person() { } Person.prototype.name = "甘宁"; Person.prototype.age = "55"; Person.prototype.gender = "猛男"; Person.prototype.introduceSelf = function () { alert("我的名字是:"+this.name+" "+"年龄:"+this.age+" 性别:"+this.gender); } var p5 = new Person(); var p6 = new Person(); p5.introduceSelf(); p5.name = "关羽"; p5.introduceSelf();//甘宁变成了关羽 alert(p5.hasOwnProperty("gender"))//false 来自实例返回True 来自原型返回false alert("gender" in p5)//true //如何判断属性来自原型? // /if(!obj.hasOwnProperty() && name in obj) name要求是字符串形式 // 3.1 简单的原型模型语法 function Person() { } Person.prototype = { constructor : Person, name : "赵飞燕", age : 15, gender : "女", introduceSelf : function () { alert("我的名字是:"+this.name+" "+"年龄:"+this.age+" 性别:"+this.gender); } } var p7 = new Person(); p7.introduceSelf(); p7.name = "金莲"; p7.introduceSelf();//名字改变了 //4. 组合模式 构造函数定义对象的属性(可变), 原型模型定义成员方法(不变通用) 推荐!!!! function Person(name, age, gender) { this.name = name; this.age = age; this.gender = gender; } Person.prototype = { constructor : Person, introduceSelf : function () { alert("我的名字是:"+this.name+" "+"年龄:"+this.age+" 性别:"+this.gender); } } var p8 = new Person("宝钗", 20, "妹纸"); var p9 = new Person("黛玉", 19, "妹纸"); p8.introduceSelf(); p9.introduceSelf();
2.继承
<script> // 继承的核心就是 CALL方法 //1.子类继承 function Animal() { this.colors = ['red','blue','green']; } function Dog() { Animal.call(this);// 子类构造函数中调用父类的构造函数 } var animal = new Animal(); var dog = new Dog(); animal.colors.push('black'); alert(animal.colors); // 'red','blue','greed','black' alert("dog:"+ dog.colors); //'red','blue','green' //2. 组合继承 :原型链对原型属性和方法继承;构造函数模式实现对实例的属性 function Animal(name) { this.name = name; this.colors = ['red','blue','green']; } Animal.prototype.introduceSelf = function () { alert(this.name); } function Cat(name, age) { Animal.call(this, name);//调用父类Animal的构造函数,实现实例属性的继承 this.age = age; } //子类继承父类的方法和属性 Cat.prototype = new Animal();//为什么不带参数name Cat.prototype.sayAge = function () { alert(this.age); } var cat = new Cat("武则天", 68); cat.colors.push("yellow"); alert(cat.colors); cat.introduceSelf(); cat.sayAge(); </script>