WM_DDE_REQUEST message

A Dynamic Data Exchange (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.

#define WM_DDE_REQUEST     0x03E6

Parameters

wParam

A 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

Requirement Value
Minimum supported client
Windows 2000 Professional [desktop apps only]
Minimum supported server
Windows 2000 Server [desktop apps only]
Header
Dde.h (include Windows.h)

See also

Reference

GlobalAddAtom

PackDDElParam

PostMessage

ReuseDDElParam

SendMessage

UnpackDDElParam

WM_DDE_ACK

WM_DDE_DATA

Conceptual

About Dynamic Data Exchange