javascript - 我想克隆一个 javascript 类。向克隆属性添加方法而不实际覆盖现有方法？

Question

我正在尝试向克隆的原型(prototype)类属性添加方法。我已粘贴下面的代码。

当我向这段代码添加方法时，它会覆盖父类(super class)中定义的内容。

<script src="http://ajax.googleapis.com/ajax/libs/prototype/1.6.0.3/prototype.js" type="text/javascript"></script>
<script type="text/javascript">
var Animal = Class.create({
    initialize: function(name, sound) {
    this.name  = name;
    this.sound = sound;
    },

    speak: function() {
    alert(this.name + " says: " + this.sound + "!");
    }
});

Animal.movement = {
    move: function(direction){
        alert('moving: ' + direction)
    }
}

var AnimalClone = { }
Object.extend(AnimalClone, Animal);

//Now i want to add 'jump' to this list of methods 
//without over writing the inherited 'move' method
AnimalClone.movement = {
    jump: function(height){
        alert('jumped:' + height)
    }
}
</script>

Answer 1

您需要扩展movement对象，而不是覆盖它:

Object.extend(AnimalClone.movement, {
    jump: function(height){
        alert('jumped:' + height)
    }
});