Re: Polymorphism
Alamelu schrieb:
Why does the below code print "Derived::Method called.", instead of
"Base::Method called." ?
How does polymorphism happen though there isn't any inheritance between
DummyBase and Derived class?
Please explain what happens internally?
Because dummyBasePtr still points to derivedObj which is of Derived type.
The point in polymorphism is that the type of the object decides about the
methods called, not the type of the pointer.
BTW, you should never use reinterpret_cast to cast the base/derived
relationship. You should use dynamic_cast instead. reinterpret_cast ignores all
object relationships. If you had casted &derivedOb to an independent class
pointer and had invoked the methods, you would most likely had a progtram crash.
In this case, you've been just lucky.
Norbert
class Base
{
public:
virtual void Method()
{
printf("Base::Method called.\n");
}
};
class Derived : public Base
{
public:
void Method()
{
printf("Derived::Method called.\n");
}
};
class DummyBase : public Base
{
public:
void Method()
{
Base::Method();
}
};
int main()
{
Derived derivedObj;
DummyBase *dummyBasePtr;
dummyBasePtr = reinterpret_cast<DummyBase *>(&derivedObj);
dummyBasePtr->Method();
return 0;
}
Thanks,
Alamelu
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