Function pointers in class scope: Problem!

[heyyo]

I have a problem:

I write a class.

There is a function, member of this class.

There is another function, member of this class, takes a “function pointer” as parameter.

Inside this class there is also a third function and it calls the second function with a function pointer to first function as parameter.

Here is the code:

#include <iostream>
using namespace std;

class Kas {

	 public:
	  int ada;

	  int firstfunction (int);

	  void secondfunction (int (*ptofunction)(int), int t);

	  void thirdfunction ();

};

void Kas::secondfunction ( int (*ptofunction)(int),int t){
	 (*ptofunction)(t);
};

int Kas::firstfunction (int s) {
	 return ada+s;
};

void Kas::thirdfunction (){
	 secondfunction(firstfunction,3);	//The problem is here!! Compiler Error
};

int main () {

    Kas den;
    den.thirdfunction();
    cout<<den.ada<<"\n";

    system("PAUSE");
    return 0;

}

how can I call the second function?

[Abramus]

In this situation you must pass firstfunction as a pointer to member function, not as a pointer to function. The corrected version of the code is shown below:

#include <iostream>
using namespace std;

class Kas {

	 public:
	  int ada;

	  int firstfunction (int);

	  void secondfunction (int (Kas::*ptofunction)(int), int t);

	  void thirdfunction ();

};

void Kas::secondfunction ( int (Kas::*ptofunction)(int),int t){
	 (this->*ptofunction)(t);
};

int Kas::firstfunction (int s) {
	 return ada+s;
};

void Kas::thirdfunction (){
	 secondfunction(&Kas::firstfunction,3);
};

int main () {

    Kas den;
    den.thirdfunction();
    cout<<den.ada<<"\n";

    system("PAUSE");
    return 0;

}

[Denis]

#include <iostream>
using namespace std;

class Kas {
public:
    int ada;

    int firstfunction (int);

    void secondfunction (int (Kas::*ptofunction)(int), int);

    void thirdfunction ();
};

void Kas::secondfunction ( int (Kas::*ptofunction)(int),int t){
    //(ptofunction)(t);
    (*this.*ptofunction)(t);
};

int Kas::firstfunction (int s) {
    return ada+s;
};

void Kas::thirdfunction (){
    secondfunction(&Kas::firstfunction,3);	//The problem is here!! Compiler Error
};

int main () {

    Kas den;
    den.thirdfunction();
    cout<<den.ada<<"\n";

    system("PAUSE");
    return 0;

}

[heyyo]

Thanks Abramus and Dennis. My mistake was at the 18th line.