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

问题描述

我正在浏览一个类似主题的讨论，但找不到我的情况...

我尝试调用带参数的父构造函数...可以

我有一个 PhysicsBody 超类，需要 aNode 作为其唯一的构造函数参数：

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

> PhysicsBody 继承了一个 DynamicBody 类。是构造函数也只需要 aNode 作为唯一的参数...就像我会在Java中做，我想调用等效于super aNode）; 似乎找不到如何。

这里是 DynamicBody class：

  //想要new PhysicsBody（this，aNode），但是失败！ 
 DynamicBody.prototype = new PhysicsBody（）; 
 DynamicBody.prototype.constructor = DynamicBody; 
 
 function DynamicBody（aNode）{
 
 //调用父构造函数失败：
 // PhysicsBody.prototype.constructor.call（this，aNode）; 
 // ... 
} 
  

解决方案

一种方法：

  function PhysicsBody（aNode）{
 this.userData = aNode; 
} 
 
 PhysicsBody.prototype.pbMethod = function（）{}; 
 
 function DynamicBody（aNode）{
 PhysicsBody.call（this，aNode）; 
} 
 
 //设置继承
 DynamicBody.prototype = Object.create（PhysicsBody.prototype）; 
 
 DynamicBody.prototype.dbMethod = function（）{}; 
  
 
 
 
 
 
 
 b 
 $ b 
  var pb = new PhysicsBody（'...'）; 
  
实例 pb 获取 userData 属性，并继承 PhysicsBody.prototype （ pbMethod  
  
 
 
 
 
 
 
当你执行
  var db = new DynamicBody ..'）; 
  
实例 db 获取 userData 属性，并继承 DynamicBody.prototype （ dbMethod 这个例子），它继承自 PhysicsBody.prototype 。
 
 
 
  
 
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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