🚀 go-pugleaf

Ray Carpenter wrote:
> Colleagues
> 
> For a process, is there a way of obtaining the main window handle HWND (as
> needed by SendMessage()) from the process handle HPROCESS (as provided by
> ShellExecuteEx())?
> 

Take a look at EnumProcesses API or here for example:

http://www.codeproject.com/threads/enumprocess.asp

or here:

http://delphi.about.com/od/windowsshellapi/l/aa080304a.htm

"Ray Carpenter" <rjcarpenter@bigpond.com> wrote in message
news:46f6e9ca@newsgroups.borland.com...

> For a process, is there a way of obtaining the main window handle
> HWND (as needed by SendMessage()) from the process handle
> HPROCESS (as provided by ShellExecuteEx())?

There is no such thing as a "main window" from the API's perspective.  Any
thread can have any number of HWNDs associated with it.

You can enumerate the running windows using EnumWindows(), using
GetWindiowLong(GWL_HINSTANCE) to get the HINSTANCE of each window and
compare that to the one returned by ShellExecuteEx().

Alternatively, you can use CreateProcess() instead of ShellExecuteEx(), and
then use GetWindowThreadProcessId() instead of GetWindowLong() to find all
of the windows that belong to the Process ID that CreateProcess() returns.

Either way, if you only find 1 matching HWND, then you likely found its
"main" window.  Note that many applications (including VCL apps) have
multiple HWNDs in their main thread, so it is up to you to manually
determine which HWND you need to send your messages to.


Gambit

Darko

Thanks for your suggestion - I will check it out.

Regards

Ray Carpenter

"Darko Miletic" <kiklop@fibertel.com.ar> wrote in message
news:46f7aad4$1@newsgroups.borland.com...
> Ray Carpenter wrote:
> > Colleagues
> >
> > For a process, is there a way of obtaining the main window handle HWND
(as
> > needed by SendMessage()) from the process handle HPROCESS (as provided
by
> > ShellExecuteEx())?
> >
>
> Take a look at EnumProcesses API or here for example:
>
> http://www.codeproject.com/threads/enumprocess.asp
>
> or here:
>
> http://delphi.about.com/od/windowsshellapi/l/aa080304a.htm

Remy

Thanks for your suggestions. You are almost an infinite source of wisdom in
these matters.

I will try out your first suggestion using the instance handle HINSTANCE
provided by ShellExecuteEx() instead of the process handle referred to in my
original posting.

Regards

Ray Carpenter


"Remy Lebeau (TeamB)" <no.spam@no.spam.com> wrote in message
news:46f7f9a2$1@newsgroups.borland.com...
>
> "Ray Carpenter" <rjcarpenter@bigpond.com> wrote in message
> news:46f6e9ca@newsgroups.borland.com...
>
> > For a process, is there a way of obtaining the main window handle
> > HWND (as needed by SendMessage()) from the process handle
> > HPROCESS (as provided by ShellExecuteEx())?
>
> There is no such thing as a "main window" from the API's perspective.  Any
> thread can have any number of HWNDs associated with it.
>
> You can enumerate the running windows using EnumWindows(), using
> GetWindiowLong(GWL_HINSTANCE) to get the HINSTANCE of each window and
> compare that to the one returned by ShellExecuteEx().
>
> Alternatively, you can use CreateProcess() instead of ShellExecuteEx(),
and
> then use GetWindowThreadProcessId() instead of GetWindowLong() to find all
> of the windows that belong to the Process ID that CreateProcess() returns.
>
> Either way, if you only find 1 matching HWND, then you likely found its
> "main" window.  Note that many applications (including VCL apps) have
> multiple HWNDs in their main thread, so it is up to you to manually
> determine which HWND you need to send your messages to.
>
>
> Gambit
>
>