Compiler Error C2843

'member' : cannot take the address of a non-static data member or method of a managed type

An instance is needed to take the address of nonstatic data members of a managed class or interface.

The following sample generates C2843:

// C2843_2.cpp
// compile with: /clr
public ref class C {
public:
   int m_i;
};

ref struct MyStruct {
   static void sf() {}
   void f() {}
};

int main() {
   MyStruct ^ps = gcnew MyStruct;
   void (__clrcall MyStruct::*F1)() = & MyStruct::f;   // C2843
   void (__clrcall MyStruct::*F2)() = & ps->f;   // C2843
   void (__clrcall MyStruct::*F3)();   // C2843

   void (__clrcall *F5)() = MyStruct::sf;   // OK
   void (__clrcall *F6)() = & ps->sf;   // OK

   interior_ptr<int> i = &C::m_i; // C2843
   C ^x = gcnew C();
   interior_ptr<int> ii = &x->m_i;
}

The following sample generates C2843:

// C2843.cpp
// compile with: /clr:oldSyntax
#using <mscorlib.dll>
public __gc class C {
public:
   int m_i;
};

__gc struct MyStruct {
   static void sf() {}
   void f() {}
};

int main() {
   MyStruct *ps = new MyStruct;
   void (__clrcall MyStruct::*F1)() = & MyStruct::f;   // C2843
   void (__clrcall MyStruct::*F2)() = & ps->f;   // C2843
   void (__clrcall MyStruct::*F3)();   // C2843

   void (__clrcall *F5)() = MyStruct::sf;   // OK
   void (__clrcall *F6)() = & ps->sf;   // OK

   int __gc *i = &C::m_i; // C2843
   C *x = new C();
   int __gc *i = &x->m_i;
}