WM_DDE_UNADVISE

A DDE client application posts a WM_DDE_UNADVISE message to inform a DDE server application that the specified item or a particular clipboard format for the item should no longer be updated. This terminates the warm or hot data link for the specified item.

WM_DDE_UNADVISE 
wParam = (WPARAM) hwnd;        // handle of posting application 
lParam = (LPARAM) lParam;      // format and item atom 
 

Parameters

hwnd

Value of wParam. Handle to the client window sending the message.

lParam

Holds the cfFormat and aItem parameters.

Parameter	Description
cfFormat	This is the LOWORD of lParam. Specifies the clipboard format of the item for which the update request is being retracted. If cfFormat is NULL, all active WM_DDE_ADVISE conversations for the item are to be terminated.
aItem	This is the HIWORD of lParam. Contains a global atom that identifies the item for which the update request is being retracted. When aItem is NULL, all active WM_DDE_ADVISE links associated with the conversation are to be terminated.

Remarks

Posting

The client application posts the WM_DDE_UNADVISE message by calling the PostMessage function, not the SendMessage function.

The client application allocates aItem by calling the GlobalAddAtom function.

Receiving

The server application posts the WM_DDE_ACK message to respond positively or negatively. When posting WM_DDE_ACK, the server can either reuse the aItem atom, or it can delete the atom and create a new one.

QuickInfo

  Windows NT: Requires version 3.1 or later.
  Windows: Requires Windows 95 or later.
  Windows CE: Unsupported.
  Header: Declared in dde.h.

See Also

Dynamic Data Exchange Overview, Dynamic Data Exchange Messages, GlobalAddAtom, PackDDElParam, PostMessage, ReuseDDElParam, SendMessage, UnpackDDElParam, WM_DDE_ACK, WM_DDE_ADVISE