Calling a function depending on a variable?

Question

Can you call a function depending on which number an integer is?

Here's what I mean:

#include <iostream>

using namespace std;

int whichFunction;

int main()
{
    cout << "Which function do you want to call?";
    cin >> whichFunction;

    function[whichFunction](); 
    //If you entered 1, it would call function1 - same with 2, 3
    //or Hihihi (of course only when whichFunction would be a string)
}


void function1()
{
    cout << "Function No. 1 was called!";
}

void function2()
{
    cout << "Function No. 2 was called!";
}

void functionHihihi()
{
    cout << "Function Hihihi was called!";
}

I know this doesn't work but I hope you get the idea.

So is there a way to do something like that?

Answer 1

Yes, there is a way to do that.

//Array for the functions
std::array<std::function<void()>, 3> functions = { &function1, &function2, &function3 };

//You could also just set them manually
functions[0] = &function1;
functions[1] = &function2;
functions[2] = &function3;

Then you can use it as a normal array:

functions[whichFunction](); //Calls function number 'whichFunction'

Do note that the functions all have to have the same signature.

---

If you do not want to use std::function for some reason, you can use function pointers.

Answer 2

switch(whichFunction) {
    case 1: function1(); break;
    case 2: function2(); break;
    case 3: function3(); break;
}