This message, posted by a client application, requests the receiving (server) application to provide the value of a data item.
wParam
Identifies the sending window.
lParam
Specifies the requested data and the clipboard format number for the data:
| Argument | Description |
| cfFormat | Low-order word of lParam. A standard or registered clipboard format number. |
| aItem | High-order word of lParam. An atom that specifies which data item is being requested from the server. |
Posting
Post the WM_DDE_REQUEST message by calling the PostMessage function, not SendMessage.
Allocate aItem by calling the GlobalAddAtom function.
Receiving
If the receiving (server) application can satisfy the request, it responds with a WM_DDE_DATA message containing the requested data. Otherwise, it responds with a negative WM_DDE_ACK message.
When responding with either a WM_DDE_DATA or WM_DDE_ACK message, reuse the aItem atom or delete it and create a new one.