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Compiler Error C3609


The latest version of this topic can be found at Compiler Error C3609.

member': a sealed or final function must be virtual

The sealed and final keywords are only allowed on a class, struct, or member function marked virtual.

The following sample generates C3609:

// C3609.cpp  
// compile with: /clr /c  
ref class C {  
   int f() sealed;   // C3609  
   virtual int f2() sealed;   // OK  

Managed Extensions for C++

The following sample generates C3609:

// C3609c.cpp  
// compile with: /clr:oldSyntax /c  
__gc class C {  
   __sealed int f();   // C3609  
   __sealed virtual int f2();   // OK