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WM_DDE_REQUEST

A DDE client application posts a WM_DDE_REQUEST message to a DDE server application to request the value of a data item.

To post this message, call the PostMessage function with the following parameters.

PostMessage( (HWND) hWnd, // handle to destination window WM_DDE_REQUEST, // message to send (WPARAM) wParam, // handle to client window (HWND) (LPARAM) lParam // format and item atom ); = Parameters =

wParam Handle to the client window sending the message.
lParam The low-order word specifies a standard or registered clipboard format. The high-order word contains an atom that identifies the data item requested from the server.

Remarks

Posting The client application allocates the atom 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, the server application can either reuse the atom or it can delete the atom and create a new one.

Requirements

  Windows NT/2000 or later: Requires Windows NT 3.1 or later.
  Windows 95/98/Me: Requires Windows 95 or later.
  Header: Declared in Dde.h; include Windows.h.

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Notebook exported on Monday, 7 July 2008, 18:56:50 PM Eastern Daylight Time