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Author LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;
Boki

2005-11-25, 3:59 am

Hi
What is this line stand for?

LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;
^^^^^^^^^
What is a LRESULT ?

Best regards,
Boki.



John Carson

2005-11-25, 3:59 am

"Boki" <bokiteam@ms21.hinet.net> wrote in message
news:OQYmtqY8FHA.952@TK2MSFTNGP12.phx.gbl
> Hi
> What is this line stand for?
>
> LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;
> ^^^^^^^^^
> What is a LRESULT ?
>
> Best regards,
> Boki.



If using VC++, you can right-click on any type and choose "Go to
Definition". This will show you that LRESULT is a typedef for a LONG_PTR. A
LONG_PTR is an integer that is the same size as a pointer. Thus it is a 32
bit integer on 32 bit platforms and a 64 bit integer on 64 bit platforms.

See here for a list of all Windows Data Types

http://msdn.microsoft.com/library/d..._data_types.asp

--
John Carson

Barry Schwarz

2005-11-25, 7:58 am

On Fri, 25 Nov 2005 14:37:15 +0800, "Boki" <bokiteam@ms21.hinet.net>
wrote:

>Hi
> What is this line stand for?
>
>LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;
>^^^^^^^^^
>What is a LRESULT ?
>

My help screen says it is a 32-bit value returned by a callback
function but does not provide any additional detail .


<<Remove the del for email>>
Brian Muth

2005-11-25, 7:02 pm


"Boki" <bokiteam@ms21.hinet.net> wrote in message
news:OQYmtqY8FHA.952@TK2MSFTNGP12.phx.gbl...
> Hi
> What is this line stand for?
>
> LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;
> ^^^^^^^^^
> What is a LRESULT ?
>


The LRESULT value that is returned from a windows procedure is an indication
to the calling code whether the windows message was handled or not. LRESULT
should be set to 0 if the windows message is handled.

Brian


Igor Tandetnik

2005-11-25, 7:02 pm

"Brian Muth" <bmuth@mvps.org> wrote in message
news:uYR$RHe8FHA.1248@TK2MSFTNGP14.phx.gbl
> "Boki" <bokiteam@ms21.hinet.net> wrote in message
> news:OQYmtqY8FHA.952@TK2MSFTNGP12.phx.gbl...
>
> The LRESULT value that is returned from a windows procedure is an
> indication to the calling code whether the windows message was
> handled or not. LRESULT should be set to 0 if the windows message is
> handled.


.... except when specified otherwise in documentation for a particular
message.
--
With best wishes,
Igor Tandetnik

With sufficient thrust, pigs fly just fine. However, this is not
necessarily a good idea. It is hard to be sure where they are going to
land, and it could be dangerous sitting under them as they fly
overhead. -- RFC 1925


bokiteam@ms21.hinet.net

2005-11-25, 7:02 pm

I got it, :D

Best regards,
Boki.

John Carson =E5=AF=AB=E9=81=93=EF=BC=9A

> "Boki" <bokiteam@ms21.hinet.net> wrote in message
> news:OQYmtqY8FHA.952@TK2MSFTNGP12.phx.gbl
>
>
> If using VC++, you can right-click on any type and choose "Go to
> Definition". This will show you that LRESULT is a typedef for a LONG_PTR.=

A
> LONG_PTR is an integer that is the same size as a pointer. Thus it is a 32
> bit integer on 32 bit platforms and a 64 bit integer on 64 bit platforms.
>
> See here for a list of all Windows Data Types
>
> http://msdn.microsoft.com/library/d...y/en-us/winpro=

g/winprog/windows_data_types.asp
>=20
> --=20
> John Carson


bokiteam@ms21.hinet.net

2005-11-25, 7:02 pm

Can you tell me the more detail?

I am newbie to VC++ and MFC, one more question, when I using a MFC, how
can I know the data members/methods...

and sometimes, I saw a lot of pXm_XXXX ..something like that, I even
don't know what is that for ...


Best regards,
Boki.

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