defaultvalue
This documentation is archived and is not being maintained.

defaultvalue

Allows specification of a default value for a typed optional parameter.

[ defaultvalue=
   value
]

Parameter

value
The default value for the parameter.

Attribute Context

Applies to Interface parameter
Repeatable No
Required attributes None
Invalid attributes None

For more information, see Attribute Contexts.

Remarks

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

Example

The following code shows an interface method using the defaultvalue attribute:

// cpp_attr_ref_defaultvalue.cpp
// compile with: /LD
#include <windows.h>

[export] typedef long HRESULT;
[export, ptr, string] typedef unsigned char * MY_STRING_TYPE;

[  uuid("479B29EE-9A2C-11D0-B696-00A0C903487A"),
   dual,
   oleautomation,
   helpstring("IFireTabCtrl Interface"),
   helpcontext(122),
   pointer_default(unique)
]
__interface IFireTabCtrl : IDispatch
{
   [bindable, propget] HRESULT get_Size(
[out, retval, defaultvalue("33")] long *nSize
);
   [bindable, propput] HRESULT put_Size(
[in] int nSize
);
};

[
   module(
      name="ATLFIRELib",
      uuid="479B29E1-9A2C-11D0-B696-00A0C903487A",
      version=1.0,
      helpstring="ATLFire 1.0 Type Library"
   )
];

See Also

IDL Attributes | Parameter Attributes | out | retval | in | pointer_default | unique | Attributes Samples

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