i''m getting a compiler error when i try to acess a variale in private from a class :O i know friends can acess private but it jsut gives me this : error C2065: ''p_Hdc'' : undeclared identifier.. here is the class def.
if i change like return p_Hdc to AP16OGL:_Hdc it gives me this -> error C2597: illegal reference to data member ''AP16OGL:_Hdc'' in a static member function. HOw can i acess those ?? thx in advance

Put the class into a header file and define the functions in a C/CPP with the header included.

It looks to me like what you want is member functions, not friend functions. Have you ever used classes and objects in C++ before?

Why are you using friend functions here? If you need to access members of a class, then use member functions for that.

Friend functions are not part of a class. They can access a class'' members through a pointer (which you don''t have) or a class'' static members. So, either make your p_Hdc member static (if you only have one instance of your class at any given time. i.e. it''s a singleton) or make the friend functions into member functions.

quote: Original post by Kippesoep
Why are you using friend functions here? If you need to access members of a class, then use member functions for that.

Friend functions are not part of a class. They can access a class'' members through a pointer (which you don''t have) or a class'' static members. So, either make your p_Hdc member static (if you only have one instance of your class at any given time. i.e. it''s a singleton) or make the friend functions into member functions.

it''s because it''s for a DLL file... and i want the dll to use the functions but dont export in case i decide to export th class

You will still have to pass an AP16OGL object to the function - as it has been pointed out, they are not member functions :

class AP1OGL{  ...  friend HDC UseDc ( const AP16OGL& obj );  ...};HDC UseDc ( const AP16OGL& obj ){  return obj.p_Hdc;} 

Your choice of identifier is quite error prone - is that a 1 or an I ?

You shouldn''t use friend functions like that, it''s fugly.

You should make the DLL functions that USE the private members friends. That way, the class internals are not exposed to non-friends, which is as it should be.
What you did is near-equivalent to making the members public, and a total violation of encapsulation principles. Making the members public would be more honest.

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