Re: C2614: Inheritance question
Jack wrote:
Hello Uli,
Thanks for the tips... But here I am with another question
class CPerson : public CPathfinder
{
bool Create(...);
...
};
class CSupervisor : public CPerson
{
virtual bool Create (...);
};
In this case, should I put the implementation code in CPerson with each
function declared as virtual and in CSupervisor as non-virtual, or the other
way round, implement code in CSupervisor and declared the derived methods as
virtual while CPerson as non-virtual (illustrated in the above snippet). I
tried the later method but with no errors reported, so I assumed that was
correct. But just in doubt if my design is correct or not?
Thanks
Jack:
Your code above is conceptually wrong, and may produce a warning on some
compilers.
Do like this
class CPerson : public CPathfinder
{
public:
virtual bool Create(...) = 0; // pure virtual
....
};
class CSupervisor : public CPerson
{
public:
virtual bool Create (...);
};
bool CSupervisor::Create(...)
{
return true;
}
The "virtual" keyword can be omitted in the derived class (CSupervisor),
but IMHO this is bad C++ style.
Now if you do
CPerson* pPerson = new CSupervisor;
pPerson->Create(...);
then CSupervisor::Create() gets called. If Create() were not declared
virtual in CPerson, the compiler would have no way to know that it
should call the derived version.
--
David Wilkinson
Visual C++ MVP
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