a class inside a class

quote:

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Original post by alnite
Can you please provide a practical example of this (game-development wise)?

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	/** Class representing merely an image file
	*/
	class CImage
	{
	protected:
		unsigned char *m_pData;
		unsigned int m_uiWidth;
		unsigned int m_uiHeight;
		unsigned int m_uiBPP;

	public:
		/** Structure representing a 2-D rectangle
		*/
		struct SRect
		{
			int iLeft, iTop, iRight, iBottom;

			SRect(int l, int t, int r, int b)
			{
				iLeft = l;
				iTop = t;
				iRight = r;
				iBottom = b;
			}

			SRect &operator = (const SRect &rkRect)
			{
				iLeft = rkRect.iLeft;
				iTop = rkRect.iTop;
				iRight = rkRect.iRight;
				iBottom = rkRect.iBottom;

				return *this;
			}
		};

	public:
		/** Constructor(s)
		*/
		CImage() 
			: m_pData(0)
		{ }

		/** Default destructor
		*/
		~CImage() 
		{ 
			if (m_pData) 
			{
				delete [] m_pData; 
				m_pData = 0;
			}
		};

            /** and bleh, it goes on. */
      

quote:

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Original post by alnite
What does that mean?

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quote:

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Can you please provide a practical example of this (game-development wise)?

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quote:

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Original post by chollida1
You would use this for an object that ownes somthing(has a)

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quote:

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Original post by alnite
Thanks for the informative replies people. This, however, raises another question, what is going to happen if I inherit a class C from class A

class C : public A
{
};


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class A
{
public: // or protected.

   class B
   {
   };
};
class C : public A
{
public:
   class D : public A::B
   {
      // Overloads for B.

   };

   // Overloads for A.

};
  

quote:

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Original post by alnite
Thanks for the informative replies people. This, however, raises another question, what is going to happen if I inherit a class C from class A

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quote:

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Will C inherit B also, considering B is protected/public?

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class A
{
public:
	class B
	{
	};
};

class C : public A
{
};

int main()
{
	A* a = new C;
	A::B* b = new C::B;
}  

quote:

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Original post by SabreMan
Edit: hold on, you didn''t mean that, did you? You can do this:

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class A
{
public:
    class B
    {
        int foo;
    };
};

class C : public A
{
    class B   // overloaded B

    {
        int newfoo;
    };
};
  

quote:

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Original post by SecondBest
As to where or why you use this particular technique; it''s used all over the STL(e.g.list::iterator)

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