Compiler Error C3721


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The latest version of this topic can be found at Compiler Error C3721.

signature': incompatible signature for event

An event was declared incorrectly. For more information, see __event.

C3721 is only reachable using /clr:oldSyntax.

The following sample generates C3721.

// C3721.cpp  
// compile with: /clr:oldSyntax /c  
using namespace System;  
public __delegate void MyDel();  
public __gc class X {  
   __event void add_E1();      // C3721  
   // try the following line instead  
   // __event void add_E1(MyDel * p);  
   __event void remove_E1();   // C3721  
   // __event void remove_E1(MyDel * p);  
   // try the following line instead  
   __event void raise_E1();