COM Map Macros

Note

The Active Template Library (ATL) continues to be supported. However, we're no longer adding features or updating the documentation.

These macros define COM interface maps.

Macro	Description
BEGIN_COM_MAP	Marks the beginning of the COM interface map entries.
END_COM_MAP	Marks the end of the COM interface map entries.

Requirements

Header: atlcom.h

BEGIN_COM_MAP

The COM map is the mechanism that exposes interfaces on an object to a client through QueryInterface.

BEGIN_COM_MAP(x)

Parameters

x
[in] The name of the class object you are exposing interfaces on.

Remarks

CComObjectRootEx::InternalQueryInterface only returns pointers for interfaces in the COM map. Start your interface map with the BEGIN_COM_MAP macro, add entries for each of your interfaces with the COM_INTERFACE_ENTRY macro or one of its variants, and complete the map with the END_COM_MAP macro.

Example

From the ATL BEEPER sample:

BEGIN_COM_MAP(CBeeper)
   COM_INTERFACE_ENTRY(IBeeper)
   COM_INTERFACE_ENTRY(IDispatch)
   COM_INTERFACE_ENTRY_TEAR_OFF(IID_ISupportErrorInfo, CBeeper2)
END_COM_MAP()

END_COM_MAP

Ends the definition of your COM interface map.

END_COM_MAP()

See also

Macros
COM Map Global Functions