javascript --- 面向对象 --- 封装

javascript中有原型对象和实例对象

如有疑问请参考：http://www.ruanyifeng.com/blog/2010/05/object-oriented_javascript_encapsulation.html

 

 

下面的代码可以用Rhino解释，代码如下：

/** * Cat的对象 * name、color；猫科动物，吃老鼠 */ print("--- --- --- 生成对象的原始模式 --- ---"); /*var Cat = { name : '', color : '' };*/ var cat1 = {}; cat1.name = "mao1"; cat1.colr = "orange"; print("cat1 : name=" + cat1.name + ", color=" + cat1.colr); print(); print("--- --- --- 原始模式的改进 --- ---"); function Cat1(name,color){ return { name:name, color:color }; }; var cat2 = Cat1("mao2", "yellow"); print("cat2 : name=" + cat2.name + ", color=" + cat2.color); print(); print("--- --- --- 构造函数模式 --- ---"); function Cat2(name, color){ this.name = name; this.color = color; } var cat3 = new Cat2("mao3", "blue"); print("cat3 : name=" + cat3.name + ", color=" + cat3.color); print("cat3.constructor == Cat2 --- " + (cat3.constructor == Cat2)); print("cat3 instanceof Cat2 --- --- " + (cat3 instanceof Cat2)); print(); print("--- --- --- 构造函数模式的问题 --- ---"); function Cat3(name, color){ this.name = name; this.color = color; this.type = "猫科动物"; this.eat = function(){ print("吃老鼠"); }; } var cat4 = new Cat3("mao4", "red"); var cat5 = new Cat3("mao5", "pink"); print("cat4 : name=" + cat4.name + ", color=" + cat4.color + ", type=" + cat4.type); cat4.eat(); print("cat5 : name=" + cat5.name + ", color=" + cat5.color + ", type=" + cat5.type); cat5.eat(); print("cat4.type == cat5.type --- --- " + (cat4.type == cat5.type)); print("cat4.eat == cat5.eat() --- --- " + (cat4.eat == cat5.eat)); print(); print("--- --- --- Prototype模式 --- ---"); function Cat4(name,color){ this.name = name; this.color = color; } Cat4.prototype.type = "猫科动物"; Cat4.prototype.eat = function(){ print("吃老鼠"); }; var cat6 = new Cat4("mao6", "green"); var cat7 = new Cat4("mao7", "gray"); print("cat6 : name=" + cat6.name + ", color=" + cat6.color + ", type=" + cat6.type); cat6.eat(); print("cat7 : name=" + cat7.name + ", color=" + cat7.color + ", type=" + cat7.type); cat7.eat(); print("cat6.type == cat7.type --- --- " + (cat6.type == cat7.type)); print("cat6.eat == cat7.eat --- --- - " + (cat6.eat == cat7.eat)); print(); print("--- --- --- Prototype模式的验证方法 --- ---"); print("Cat4.prototype.isPrototypeOf(cat6) --- " + Cat4.prototype.isPrototypeOf(cat6)); print("Cat4.prototype.isPrototypeOf(cat5) --- " + Cat4.prototype.isPrototypeOf(cat5)); print('cat6.hasOwnProperty("name") --- --- ' + cat6.hasOwnProperty("name")); print('cat6.hasOwnProperty("type") --- --- ' + cat6.hasOwnProperty("type")); print('"name" in cat7 --- ---' + ("name" in cat7)); print('"colr" in cat7 --- ---' + ("colr" in cat7)); for(var prop in cat7) { print("\tcat7["+prop+"] = " + cat7[prop]); } 

 

 

打印结果如下：

 

--- --- --- 生成对象的原始模式 --- ---
cat1 : name=mao1, color=orange

--- --- --- 原始模式的改进 --- ---
cat2 : name=mao2, color=yellow

--- --- --- 构造函数模式 --- ---
cat3 : name=mao3, color=blue
cat3.constructor == Cat2 --- true
cat3 instanceof Cat2 --- --- true

--- --- --- 构造函数模式的问题 --- ---
cat4 : name=mao4, color=red, type=猫科动物
吃老鼠
cat5 : name=mao5, color=pink, type=猫科动物
吃老鼠
cat4.type == cat5.type --- --- true
cat4.eat == cat5.eat() --- --- false

--- --- --- Prototype模式 --- ---
cat6 : name=mao6, color=green, type=猫科动物
吃老鼠
cat7 : name=mao7, color=gray, type=猫科动物
吃老鼠
cat6.type == cat7.type --- --- true
cat6.eat == cat7.eat --- --- - true

--- --- --- Prototype模式的验证方法 --- ---
Cat4.prototype.isPrototypeOf(cat6) --- true
Cat4.prototype.isPrototypeOf(cat5) --- false
cat6.hasOwnProperty("name") --- --- true
cat6.hasOwnProperty("type") --- --- false
"name" in cat7 --- ---true
"colr" in cat7 --- ---false
    cat7[name] = mao7
    cat7[color] = gray
    cat7[type] = 猫科动物
    cat7[eat] = 
function () {
    print("\u5403\u8001\u9f20");
}

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