BCGCBPRODLLEXPORT UINT BCGM_CALENDAR_ON_MONTHCHANGED

This message is sent to owner of calendar bar control when selected month has been changed.

Parameters

wParam	This parameter is not used.
lParam	a handle to calendar bar control.

Returns

The return value is ignored.

You should process this message to receive notifications from CBCGPCalendarBar objects when selection (selected month) has been changed.