Re: Definition of Pure Virtual Function
"Anand Choubey" <AnandChoubey@discussions.microsoft.com> wrote in
message news:8BBD22D6-216F-43EE-A4D0-A3B2EA2D51C1@microsoft.com
Hi,
As we read in all C++ Docs that definition of pure virtual fucntion
is given in driver class only. But following code is compiling and
running but there is definition of pure virtual function.
Please tell what is purpose of defition of pure virtual function.
class CA
{
public:
virtual void f() = 0;
};
void CA::f()
{
}
class CB : CA
{
public:
virtual void f();
};
void CB::f()
{
}
--
With regards
thanks
Anand Choubey
One use of definitions to go with pure virtual functions is to provide code
needed by all derived classes, e.g.,
class Base
{
public:
virtual void foo()=0;
};
void Base::foo()
{
cout << "common code supplied by base class\n";
}
class DerivedA : public Base
{
public:
virtual void foo()
{
Base::foo();
cout << "code supplied by DerivedA class\n";
}
};
class DerivedB : public Base
{
public:
virtual void foo()
{
Base::foo();
cout << "code supplied by DerivedB class\n";
}
};
int main()
{
DerivedA a;
DerivedB b;
a.foo();
b.foo();
return 0;
}
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