ms_union

 

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Controls the network data representation alignment of nonencapsulated unions.

  
[ms_union]  
  

The ms_union C++ attribute has the same functionality as the ms_union MIDL attribute.

The following code shows the placement of ms_union:

// cpp_attr_ref_ms_union.cpp  
// compile with: /LD  
#include <unknwn.h>  
[object, ms_union, uuid("00000000-0000-0000-0000-000000000001")]  
__interface IFireTabCtrl {  
   HRESULT DisplayString([in, string] char * p1);  
};  
  
[export, switch_type(short)] union _WILLIE_UNION_TYPE  {  
   [case(24)]  
      float fMays;  
   [case(25)]  
      double dMcCovey;  
   [default]  
      int x;  
 };  
  
[public] typedef _WILLIE_UNION_TYPE WILLIE_UNION_TYPE;  
  
[module(name="ATLFIRELib")];  

Attribute Context

Applies toNonencapsulated unions
RepeatableNo
Required attributesNone
Invalid attributesdispinterface

For more information, see Attribute Contexts.

IDL Attributes
Typedef, Enum, Union, and Struct Attributes
Attributes Samples

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