|
Overview |
|
|
|
Group |
|
|
|
Quick Info
Windows NT
| Yes
| Win95
| Yes
| Win32s
| Yes
| Import Library
| -
| Header File
| dde.h
| Unicode
| No
| Platform Notes
| None
|
|
|
WM_DDE_INITIATE
A DDE client application sends a WM_DDE_INITIATE message to initiate a
conversation with a server application responding to the specified application and
topic names. Upon receiving this message, all server applications with names that
match the specified application and that support the specified topic are
expected to acknowledge it. (For more information, see the WM_DDE_ACK message.)
WM_DDE_INITIATE
wParam = (WPARAM) hwnd; // handle of posting appl.
lParam = MAKELPARAM(aApp, aTopic); // appl. and topic atoms
Parameters
hwnd
Value of wParam. Identifies the client window sending the message.
aApp
Value of the low-order word of lParam. Contains an atom that identifies the application with which a conversation
is requested. The application name cannot contain slashes (/) or backslashes
(\). These characters are reserved for network implementations. If aApp is NULL, a conversation with all applications is requested.
aTopic
Value of the high-order word of lParam. Contains an atom that identifies the topic for which a conversation is
requested. If the topic is NULL, conversations for all available topics are
requested.
Remarks
If aApp is NULL, any server application can respond. If aTopic is NULL, any topic is valid. Upon receiving a WM_DDE_INITIATE request with
the aTopic parameter set to NULL, a server must send a WM_DDE_ACK message for each of the topics it supports.
Sending
The client application sends WM_DDE_INITIATE by calling the SendMessage function, not the PostMessage function. The client broadcasts the message to all top-level windows by
setting the first parameter of SendMessage to 1.
If the client application has already obtained the window handle of the
desired server, it can send WM_DDE_INITIATE directly to the server window by passing
the server's window handle as the first parameter of SendMessage.
The client application allocates aApp and aTopic by calling GlobalAddAtom.
When SendMessage returns, the client application must delete the aApp and aTopic atoms.
Receiving
To complete the initiation of a conversation, the server application must
respond with one or more WM_DDE_ACK messages, where each message is for a separate
topic. When sending WM_DDE_ACK message, the server should create new aApp and aTopic atoms; it should not reuse the atoms sent with WM_DDE_INITIATE.
See Also
GlobalAddAtom, GlobalAlloc, PostMessage, SendMessage, WM_DDE_ACK
Related Links
Software for Delphi and C++ Builder developers
Software for Visual Studio .NET developers
Software for Visual Basic 6 developers
Delphi Tips&Tricks
MegaDetailed.NET
TMS Scripter Studio Pro components for Delphi/C++Builder
More Online Helps
Win32 Multimedia Programmer's Reference (mmedia.hlp)
OLE Programmer's Reference (ole.hlp)
Microsoft Windows Pen API Programmer's Reference (penapi.hlp)
Microsoft Windows Sockets 2 Reference (sock2.hlp)
Microsoft Windows Telephony API (TAPI) Programmer's Reference (tapi.hlp)
Unix Manual Pages
|