[python-win32] Re: Help on using win32api.SendMessage to send keystrokes

[Tim Roberts]

On Wed, 30 Mar 2005 20:46:43 -0500, Daniel F <nanotube at gmail.com> wrote:

>Well... i figured it out - turns out sending the keystrokes to the top
>window of notepad didnt work, but sending them to the Edit child
>window of notepad did the trick.
>
>But this brings me to another question, although of a less urgent
>manner. i had to send WM_CHAR messages, rather than WM_KEYDOWN/KEYUP
>in order to get it to work. I have nothing against WM_CHAR, as long as
>everything works, but i am just curious why i was not able to achieve
>the same effect with the WM_KEYDOWN/KEYUP pair? any takers?
>

It depends entirely on what the application expects.  When the keyboard 
driver sends keystrokes, the generic keyboard driver translates the key 
codes to characters, if possible.  It will send WM_KEYDOWN, then WM_CHAR 
(if an ASCII translation exists), then WM_KEYUP.  Applications can 
choose which ones they want to handle.

In your case, you are bypassing the keyboard driver stack entirely.  The 
standard edit control, which is all Notepad is, apparently looks only at 
WM_CHAR.  There is no a priori method for figuring out which one is 
required.  If you need a general solution, you send all three.  In this 
case, since you want a specific solution, you can send just WM_CHAR.

-- 
- Tim Roberts, timr at probo.com
  Providenza & Boekelheide, Inc.