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case (C++)

Used with the switch_type attribute in a union.

[ case(
      value
) ]

Parameters

  • value
    A possible input value for which you want to provide processing. The type of value can be one of the following types:

    • int

    • char

    • boolean

    • enum

    or an identifier of such a type.

Remarks

The case C++ attribute has the same functionality as the case MIDL attribute. This attribute is only used with the switch_type attribute.

Example

The following code shows a use of the case attribute:

// cpp_attr_ref_case.cpp
// compile with: /LD
#include <unknwn.h>
[export]
struct SizedValue2 {
   [switch_type(char), switch_is(kind)] union {
      [case(1), string]
          wchar_t* wval;
      [default, string]
          char* val;
   };
    char kind;
};
[module(name="ATLFIRELib")];

Requirements

Attribute Context

Applies to

Member of a class or struct

Repeatable

No

Required attributes

None

Invalid attributes

None

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

See Also

Concepts

IDL Attributes

Typedef, Enum, Union, and Struct Attributes

Class Attributes

ATL Samples