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Compiler Error C3624

 

The latest version of this topic can be found at Compiler Error C3624.

type': use of this type requires a reference to assembly 'assembly'

An assembly (reference) needed to compile your code was not specified; pass the assembly to the #using directive.

The following sample generates C3624:

// C3624.cpp  
// compile with: /clr /c  
#using <System.Windows.Forms.dll>  
  
// Uncomment the following 2 lines to resolve.  
// #using <System.dll>  
// #using <System.Drawing.dll>  
  
using namespace System;  
  
public ref class MyForm : public Windows::Forms::Form {};   // C3624  

The following sample generates C3624:

// C3624_b.cpp  
// compile with: /clr:oldSyntax /c  
#using <System.Windows.Forms.dll>  
  
// Uncomment the following 2 lines to resolve.  
// #using <System.dll>  
// #using <System.Drawing.dll>  
  
using namespace System;  
  
public __gc class MyForm : public Windows::Forms::Form {};   // C3624  

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