This was a bit fiddly to get right. I got inspiration from How do I create and use an array of pointer-to-member-function?
Based on my post about Function pointers / function callbacks / function variables I modified it to work with class functions:
class foo {
public:
void doAction0 ()
{
Serial.println (0);
}
void doAction1 ()
{
Serial.println (1);
}
void doAction2 ()
{
Serial.println (2);
}
void doAction3 ()
{
Serial.println (3);
}
void doAction4 ()
{
Serial.println (4);
}
// typedef for class function
typedef void (foo::*GeneralFunction) ();
// array of function pointers
GeneralFunction doActionsArray [5] =
{
&foo::doAction0,
&foo::doAction1,
&foo::doAction2,
&foo::doAction3,
&foo::doAction4,
};
}; // end of class foo
void setup ()
{
Serial.begin (115200);
Serial.println ();
Serial.println (F("Starting"));
// test instance of foo
foo bar;
for (int i = 0; i < 5; i++)
{
// get member function pointer from array
foo::GeneralFunction f = bar.foo::doActionsArray [i];
// call the function
(bar.*f) ();
} // end of for loop
} // end of setup
void loop () { }
This compiles OK and prints:
Starting
0
1
2
3
4
Amended answer
I was wondering why you needed to specify bar in this line above:
foo::GeneralFunction f = bar.foo::doActionsArray [i];
The reason is that the code above had the array as non-static, and thus a copy belonged to each instance of the class. This doesn't make a huge amount of sense, so the modified code below makes the array static and const. That is, the array should be the same for every instance of foo and also never change.
Modified code below:
class foo {
public:
void doAction0 ()
{
Serial.println (0);
}
void doAction1 ()
{
Serial.println (1);
}
void doAction2 ()
{
Serial.println (2);
}
void doAction3 ()
{
Serial.println (3);
}
void doAction4 ()
{
Serial.println (4);
}
// typedef for class function
typedef void (foo::*GeneralFunction) ();
static const GeneralFunction doActionsArray [5];
}; // end of class foo
// array of function pointers
const foo::GeneralFunction foo::doActionsArray [5] =
{
&foo::doAction0,
&foo::doAction1,
&foo::doAction2,
&foo::doAction3,
&foo::doAction4,
};
void setup ()
{
Serial.begin (115200);
Serial.println ();
Serial.println (F("Starting"));
// test instance of foo
foo bar;
for (int i = 0; i < 5; i++)
{
// get member function pointer from array
foo::GeneralFunction f = foo::doActionsArray [i];
// call the function
(bar.*f) ();
}
} // end of setup
void loop () { }
This will also save RAM, as the array of function pointers only exists once, not once per instance of the class.
