Virtual Overloaded Function Question...

[John Mancini]

I was wondering if somebody can explain why the following doesn't work: class base { public: virtual void fn(int nData) ( /* Do Something */ }; virtual void fn(char * pszData) { /* Do Something */ }; } class derived : public base { public: virtual void fn(char * pszData) { /* Do Something */ }; } void MyFunction { derived myderived; int nData = 5; myderived.fn(nData); } The compiler complains about myderived.fn(nData). It says.... "error C2664: 'fn' : cannot convert parameter 1 from 'int' to 'char *'. ...." Why doesn't it just use the base class fn(int nData)???? Am I doing something wrong or is this C++ behaviour? Thanks in Advance Chris Mancini

[Mike Dunn]

Polymorphism only kicks in if you are accessing your C++ object through a pointer. This is what you need to do: { derived myDerived, *pDerived; int nData = 5; pDerived = &myDerived; pDerived->fn(nData); } ================== The original message was: I was wondering if somebody can explain why the following doesn't work:

class base
{
public:
virtual void fn(int nData) ( /* Do Something */ };
virtual void fn(char * pszData) { /* Do Something */ };
}

class derived : public base
{
public:
virtual void fn(char * pszData) { /* Do Something */ };
}

void MyFunction
{
derived myderived;
int nData = 5;

myderived.fn(nData);
}

The compiler complains about myderived.fn(nData). It says....
"error C2664: 'fn' : cannot convert parameter 1 from 'int' to 'char *'. ...."

Why doesn't it just use the base class fn(int nData)????
Am I doing something wrong or is this C++ behaviour?

Thanks in Advance
Chris Mancini

[Prabhat Tripathi]

You have actually overrided the function 'fn' and using it as a overloaded function. Check it out. Regards, Prabhat ================== The original message was: I was wondering if somebody can explain why the following doesn't work:

class base
{
public:
virtual void fn(int nData) ( /* Do Something */ };
virtual void fn(char * pszData) { /* Do Something */ };
}

class derived : public base
{
public:
virtual void fn(char * pszData) { /* Do Something */ };
}

void MyFunction
{
derived myderived;
int nData = 5;

myderived.fn(nData);
}

The compiler complains about myderived.fn(nData). It says....
"error C2664: 'fn' : cannot convert parameter 1 from 'int' to 'char *'. ...."

Why doesn't it just use the base class fn(int nData)????
Am I doing something wrong or is this C++ behaviour?

Thanks in Advance
Chris Mancini