requires_category

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Specifies the required component categories of the target class.

  
     [ requires_category(   
  requires_category  
) ]  

Parameters

requires_category
The ID of the required category.

The requires_category C++ attribute specifies the component categories required by the target class. For more information, see REQUIRED_CATEGORY.

This attribute requires that the coclass, progid, or vi_progid attribute (or another attribute that implies one of these) also be applied to the same element.

The following code requires that the object implement the Control category.

// cpp_attr_ref_requires_category.cpp  
// compile with: /LD  
#define _ATL_ATTRIBUTES  
#include "atlbase.h"  
#include "atlcom.h"  
  
[module (name="MyLibrary")];  
  
[ coclass, requires_category("CATID_Control"),  
  uuid("1e1a2436-f3ea-4ff3-80bf-5409370e8144")]  
class CMyClass {};  

Attribute Context

For more information about the attribute contexts, see Attribute Contexts.

COM Attributes
implements_category
Attributes Samples