source (C++)

On a class, specifies the COM object's source interfaces for connection points. On a property or method, indicates that the member returns an object or VARIANT that is a source of events.

[ source(
      interfaces
) ]

Parameters

  • interfaces
    One or more interfaces that you specify when you apply the source attribute to a class. This parameter is not used when source is applied to a property or method.

Remarks

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

You can use the default attribute to specify the default source interface for an object.

Example

// cpp_attr_ref_source.cpp
// compile with: /LD
#include "windows.h"
#include "unknwn.h"
[module(name="MyLib")];

[object, uuid(11111111-1111-1111-1111-111111111111)]
__interface b
{
   [id(0), propget, bindable, displaybind, defaultbind, requestedit]
   HRESULT get_I([out, retval]long *i);
};

[object, uuid(11111111-1111-1111-1111-111111111131)]
__interface c
{
   [id(0), propget, bindable, displaybind, defaultbind, requestedit] 
   HRESULT et_I([out, retval]long *i);
};

[coclass, default(c), uuid(11111111-1111-1111-1111-111111111132)]
class N : public b
{
};

[coclass, source(c), default(b, c), uuid(11111111-1111-1111-1111-111111111133)]
class NN : public b
{
};

Requirements

Attribute Context

Applies to

class, struct, interface

Repeatable

No

Required attributes

coclass (when applied to class or struct)

Invalid attributes

None

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

See Also

Concepts

IDL Attributes

Class Attributes

Method Attributes

coclass

ATL Samples