Member function pointer to a member function

[joshuawoodz]

Trying to create a class that has a member function pointer that points to a member function.
Here is a basic example of what I'm trying to do:

class X
{
public:
X();
short myFunction(void*, DWORD, byte);

short (&X::fptr)(void*, DWORD, byte);
};

X::X()
{
fptr = &X::myFunction;
}

in the main program
X myx;
char *a;
DWORD b;
byte c;

myx.*fptr(a, b, c); -> on compile I get 'fptr': identifier not found

I have tried using typedef in various ways and have had no success. Any help would be awesome!

[Paul McKenzie]

Trying to create a class that has a member function pointer that points to a member function.
Here is a basic example of what I'm trying to do:

Usage of typedef makes this a lot simpler:

class X
{
    public:
    typedef short (X::*ptrFn)(void*, DWORD, byte);
    X();
    short myFunction(void*, DWORD, byte);
    ptrFn fptr;
};

So now there is a member variable of type "ptrFn" called fptr.

In main()

int main()
{
    X myx;
    char *a;
    DWORD b;
    byte c;
    X::ptrFn fn = myx.fptr;
    (myx.*fn)(a, b, c); 
}

This now compiles. Note how the expression is broken up in main() to see how this all works.

Now, you can do a substitution:

int main()
{
    X myx;
    char *a;
    DWORD b;
    byte c;
    (myx.*(myx.fptr))(a, b, c); 
}

This now compiles. All I did was substitute back into the expression the declaration of "fn".

Regards,

Paul McKenzie

[D_Drmmr]

Have a look at http://www.parashift.com/c++-faq-lit....html#faq-33.6