Compiler Warning C4687

'class': a sealed abstract class cannot implement an interface 'interface'

Remarks

A sealed, abstract type is typically only useful to hold static member functions.

For more information, see abstract and sealed.

C4687 is issued as an error by default. You can suppress C4687 with the warning pragma. If you are certain that you want to implement an interface in a sealed, abstract type, you can suppress C4687.

Example

The following example generates C4687.

// C4687.cpp
// compile with: /clr /c
interface class A {};

ref struct B sealed abstract : A {};   // C4687
ref struct C sealed : A {};   // OK
ref struct D abstract : A {};   // OK