Question

I’ve a C# class library with overloaded methods, and one method has a ref parameter and the other has a value parameter. I can call these methods in C#, but I can’t get it right in C++/CLI. It’s seems compiler can’t distinguish these two methods.

Here is my C# code

namespace test {
    public class test {
        public static void foo(int i)
        {
            i++;
        }
        public static void foo(ref int i)
        {
            i++;
        }
    }
}

and my C++/CLI code

int main(array<System::String ^> ^args)
{
    int i=0;
    test::test::foo(i);     //error C2668: ambiguous call to overloaded function
    test::test::foo(%i);    //error C3071: operator '%' can only be applied to an instance of a ref class or a value-type
    int %r=i;
    test::test::foo(r);     //error C2668: ambiguous call to overloaded function
    Console::WriteLine(i);
    return 0;
}

I know in C++ I can’t declare overload functions where the only difference in the function signature is that one takes an object and another takes reference to an object, but in C# I can.

Is this a feature supported in C# but not in C++/CLI? Is there any workaround?

Answer 1

As a workaround you could build a C# helper class that you use in C++/CLI

namespace test
{
    public class testHelper
    {
        public static void fooByVal(int i)
        {
            test.foo(i);
        }

        public static void fooByRef(ref int i)
        {
            test.foo(ref i);
        }
    }
}