Export (0) Print
Expand All
Expand Minimize

Compiler Warning (level 4) C4680

'class' : coclass does not specify a default interface

A default interface was not specified for a class that was marked with the coclass attribute. In order for an object to be useful, it must implement an interface.

The following sample generates C4680 and shows one way to resolve it:

// C4680.cpp
// compile with: /W4
#include <windows.h>

[ object, uuid(373a1a4c-469b-11d3-a6b0-00c04f79ae8f) ]
__interface IMyIface1
   HRESULT f1();

[ object, uuid(37331a4c-469b-11d3-a6b0-00c04f79ae8f) ]
__interface IMyIface2
   HRESULT f1();

// to resolve C4680, specify a source interface also
// for example, default(IMyIface1, IMyface2)
[ coclass, uuid(373a1a4d-469b-11d3-a6b0-00c04f79ae8f), default(IMyIface1), source(IMyIface1) ]
class CMyClass : public IMyIface1
{   // C4680

int main()
© 2014 Microsoft