继承父构造函数的参数 [英] Inherit parent constructor arguments

问题描述

我在浏览讨论了类似的话题，但找不到我的情况...

我试图用参数调用父构造......似乎无法得到它的权利。

我有一个 PhysicsBody 超类需要阳极作为其唯一的构造函数的参数：

 函数PhysicsBody（阳极）{
    this.userData =阳极;
    // ...
}
 

这一点 PhysicsBody 继承了 DynamicBody 类。是构造也需要阳极作为唯一参数...喜欢我会在Java中做到这一点，我喜欢的东西相当于调用超级（阳极）; 似乎无法找出如何

这里的 DynamicBody 类：

  //想给新PhysicsBody（这一点，阳极），但失败！
DynamicBody.prototype =新PhysicsBody（）;
DynamicBody.prototype.constructor = DynamicBody;功能DynamicBody（阳极）{    //调用父类的构造也失败了：
    // PhysicsBody.prototype.constructor.call（这一点，阳极）;
    // ...
}
 

解决方案

要做到这一点的方法之一：

 函数PhysicsBody（阳极）{
    this.userData =阳极;
}PhysicsBody.prototype.pbMethod =函数（）{};功能DynamicBody（阳极）{
    PhysicsBody.call（这一点，阳极）;
}//设置继承
DynamicBody.prototype =的Object.create（PhysicsBody.prototype）;DynamicBody.prototype.dbMethod =函数（）{};
 

---

现在，当你做

  VAR PB =新PhysicsBody（'...'）;
 

实例 PB 得到了用户数据属性，并且还继承了 PhysicsBody的方法。原型（ pbMethod 在这种情况下）。

---

当你做

 变种DB =新DynamicBody（'...'）;
 

实例分贝得到了用户数据属性，并且还继承了 DynamicBody的方法。原型（ dbMethod 在这种情况下），这反过来从 PhysicsBody.prototype 继承。

I'm browsing the discussion for a similar topic, but can't find my situation...

Am trying call parent constructors with parameters... can't seem to get it right.

I have a PhysicsBody superclass that takes aNode as its only constructor argument:

function PhysicsBody(aNode) {
    this.userData = aNode;
    // ...
}

Of this PhysicsBody inherits a DynamicBody class. Is constructor also takes aNode as only argument... Like I would do it in Java, I'd love to call something equivalent to "super(aNode"); Can't seem to find out how.

Here's the DynamicBody class:

// Wanted to give "new PhysicsBody(this, aNode)", but that fails!
DynamicBody.prototype = new PhysicsBody();
DynamicBody.prototype.constructor=DynamicBody;

function DynamicBody(aNode) {

    // calling the parent constructor fails too:
    // PhysicsBody.prototype.constructor.call(this, aNode);
    //...
}

解决方案

One way to do it:

function PhysicsBody( aNode ) {
    this.userData = aNode;
}

PhysicsBody.prototype.pbMethod = function () {};

function DynamicBody( aNode ) {
    PhysicsBody.call( this, aNode );
}

// setting up the inheritance
DynamicBody.prototype = Object.create( PhysicsBody.prototype );

DynamicBody.prototype.dbMethod = function () {};

---

Now, when you do

var pb = new PhysicsBody( '...' );

the instance pb gets a userData property and also inherits the methods from PhysicsBody.prototype (pbMethod in this case).

---

When you do

var db = new DynamicBody( '...' );

the instance db gets a userData property and also inherits the methods from DynamicBody.prototype (dbMethod in this case), which in turn inherits from PhysicsBody.prototype.

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