I guess this is a simple question, but my google search did not result in any good answers. So maybe you guys have a quick solution.

I have the following C++ sample function

- Code: Select all
`double mySum(double &arg1, double &arg2)`

{

arg1++;

return arg1+arg2;

}

I've built the xll (of course I'm using xlw) and use the Addin in Excel. In Excel I have 3 cells

A1: 1

A2: 3

A3: =mySum(A1;A2)

A3 displays the correct sum (=5), but A1 is not incremented (should be 2).

Somehow the call-by-reference in the C++ function does not work.

How do I have to make that function call?

Or alternatively: how do I change the A1 cell value from C++?

Cheers

Sean