Prevent class inheritance in C++ -


Recently one of my friends asked me that C ++ wanted to thwart the compilation.

I was thinking about it and got 3 answers. Not sure which is the best.

1) Private Creator (s) 

  Class CBase {Public: Fixed CBase * CreateInstance () {CBBS * B1 = New CBBs (); Return B1; } Private: cb () {} CBbase (CBbase3) {} CBC and operator = (CBBSE End) {}};

2) Using the CSell Base Class, Personal CTOR & amp; Virtual Legacy 

  class CSealed {Private: CSealed () {} Friend Class CBase; }; Class CBBSE: Virtual CSealed {Public: CBase () {}};

3) Using a CSealed Base Class, Protected CTOR & amp; Virtual Legacy 

  class CSealed {Secure: CSealed () {}}; Class CBBSE: Virtual CSealed {Public: CBase () {}};

All the above methods ensure that the CBBSS class can not be inherited. My question is:

1) Which is the best way? Are there any other methods available?

2) Method 2 & amp; Why is it so long as the CSealed class inherited in heritage will not work? What does something with vdisp ptr do ??

PS:

The above program was compiled in the MS C ++ Compiler (Visual Studio). Reference:

As C ++, you can add the last keyword to your square, for example For 

  class CBase final {...

The main reason for this is that I can see to do this (and I look for this question I have come in) to mark a class as non subclassable so that you can safely use a non-virtual constructor and can not completely escape from a Vettel.


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