How do I send/post messages?

Posted on 1998-10-31
Last Modified: 2010-08-05
I have a main form with 3 panels. I would like one panel to send a new WM message to the other panels.
I found some help about adding event handlers but I don't know how to actually send the message (after filling the lParam and wParam parametrs).
An example would be very helpful.

Question by:tommyq
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Author Comment

ID: 1345175
Edited text of question

Accepted Solution

ZifNab earned 50 total points
ID: 1345176
Hi tommyq,

you can use PostMessage or SendMessage.

SendMessage waits until message is processed, postmessage puts the message in the qeue and returns.

With Objects you can also use Perform. (like sendmessage, it waits until message is processed) :

RetVal := ObjectName.Perform(MessageID, wParam, lParam);


 SendMessage(hWnd, MessageID, wParam, lParam);

 PostMessage(hWnd, MessageID, wParam, lParam);

Regards, Zif.

Author Comment

ID: 1345177
Thanks for your prompt reply, ZifNab.

How do I get the hWnd of a certain control?


Expert Comment

ID: 1345178
Hi tommyq,

eg. Form1.Handle

Regards, Zif.

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