readonly (C++)


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Prohibits assignment to a data member.


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

If you want to prohibit modification of a method parameter, then use the in attribute.

The following code shows a use of the readonly attribute:

// cpp_attr_ref_readonly.cpp  
// compile with: /LD  
[idl_quote("midl_pragma warning(disable:2461)")];  
#include "unknwn.h"  
[dispinterface, uuid(11111111-1111-1111-1111-111111111111)]  
__interface IFireTabCtrl  
   [readonly, id(1)] int i();  

Attribute Context

Applies toInterface method
Required attributesNone
Invalid attributesNone

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

IDL Attributes
Data Member Attributes
Attributes Samples