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. Identifies 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.
See Also
GlobalAddAtom, PackDDElParam, PostMessage, ReuseDDElParam, SendMessage, UnpackDDElParam, WM_DDE_ACK, WM_DDE_ADVISE