polymorphism in simple classes
In this thread I have proved that
PHP Code:
class A
{
public:
static void func(){std::cout<<"A\n";}
};
class B:public A
{
public:
virtual void func(){A::func();}
};
class C:public B
{
public:
virtual void funx(){func();}
};
class D:public C
{
public:
virtual void func(){std::cout<<"CC\n";}
void Call(){funx();}
};
int _tmain(int argc, _TCHAR* argv[])
{
D b;
b.Call();
return 0;
}
the D::func is not polymophically called in the client code and in C++ I can eliminate "virtual" key, as it is indifferent, but in managed C++
PHP Code:
ref class A
{
public:
static void func(){Console::WriteLine("A");}
};
ref class B:public A
{
public:
virtual void func(){A::func();}
};
ref class C:public B
{
public:
virtual void funx(){func();}
};
ref class D:public C
{
public:
virtual void func() override {Console::WriteLine("CC");}
void Call(){funx();}
};
I can't eliminate the virtual key in the D class. I wonder is this D::func polymorphically created once called ? Thank you
Re: polymorphism in simple classes
The fact that, unlike ANSI C++, the virtual keyword is not optional in C++/CLI when overriding a virtual base class member fuction (as well as the necessity of the override keyword in this context, that you already have recognized), simply is one of the syntactic differences between the two languages. AFAICT at least part of the reason why this requirement was introduced is enforcing code clarity: When you override a virtual base class function in ANSI C++ and omit the virtual keyword since it's implied anyway, readers of your code may miss the fact that it's a virtual function entirely, unless they also look at the base class declaration.
Also, you can do some rather funky things with virtual funtions in C++/CLI that are not (at least not the same way) possible in ANSI C++. For more info about this see http://msdn.microsoft.com/en-us/libr...v=vs.100).aspx and http://msdn.microsoft.com/en-us/libr...v=vs.100).aspx.
Quote:
Originally Posted by
terminalXXX
I wonder is this D::func polymorphically created once called ? Thank you
I have no idea what you mean by this, though. :ehh:
