send usermessage to another form with postmessage

[Snamelisch]

How can I sent userdefined message to another form usign Postmessage?

[Oafo]

You mean that the user can select what message he/she wants to send to a handle, then they press a button and it sends the message?

[Megatron]

You can create your own message by adding some constant to WM_USER e.g

WM_MYMSG = WM_USER + 100

Just make sure you put that in both apps.

[Snamelisch]

Then follows the next question:

How can I use the parameters lparam and wparam to transport date for me?

This does not become clear in the documentation that I have found.