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Neil Stevens - 31 Oct 2005 09:43 GMT

Hi All,

I am in the process of creating a message filter for an application that i
am writing, this is really just a question for information on the LParam
value of the PreFilterMessage method.

Now, i know that this parameters value depends on the message, but is there
any information anywhere that details what the structure of the LParam
parameter is for each message. I know that the WM_CREATE messages LParam
value is a CREATESTRUCT structure, but i don't know any others.

I would ideally like to know the structure of the LParam value for key
messages and mouse messages as these are what i will be globally handling in
my application.

Any help or information will be greatly appreciated.

Thanks in advance
Neil

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Lars Behrmann - 31 Oct 2005 11:38 GMT

Hi Neil,

last week i had a smilar problem. Which we discussed
in the german c# newsgroup, but as result there is a
"full" list of all windows messages, now. Maybe that helps.

http://dzaebel.net/WM_Msg_NET.htm

Cheers
Lars Behrmann

_________________
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Neil Stevens schrieb:

> Hi All,
>
[quoted text clipped - 15 lines]
> Thanks in advance
> Neil

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Neil Stevens - 31 Oct 2005 12:15 GMT

Thanks Lars, but i already have the values for all the windows messages,
taken from the C++ header files.

What i'm looking for is the structure definitions for the key and mouse
messages, these are the structs that are sent in the LParam value of the
Message structure.

For example, byte 24 of the LParam value for a KeyDown message defines which
Ctrl, Shift or Alt key is pressed (Left or Right key), i know that there are
other values such as the key state and the key code and the repeat count.

Found this in the .NET MSDN
ms-help://MS.VSCC.v80/MS.MSDNQTR.v80.en/MS.MSDN.v80/MS.WIN32COM.v10.en/winui/winui/windowsuserinterface/userinput/keyboardinput/keyboardinputreference/keyboardinputmessages/wm_keydown.htm

Does anyone know where i can find the structure definitions for the key and
mouse messages, or can anyone tell me what they are.

Thanks in advance
Neil

> Hi Neil,
>
[quoted text clipped - 36 lines]
>> Thanks in advance
>> Neil

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Larry Lard - 31 Oct 2005 13:03 GMT

> Thanks Lars, but i already have the values for all the windows messages,
> taken from the C++ header files.
[quoted text clipped - 9 lines]
> Found this in the .NET MSDN
> ms-help://MS.VSCC.v80/MS.MSDNQTR.v80.en/MS.MSDN.v80/MS.WIN32COM.v10.en/winui/winui/windowsuserinterface/userinput/keyboardinput/keyboardinputreference/keyboardinputmessages/wm_keydown.htm

You are misreading that page (btw URLs to the internet documentation
are more helpful as different people's local MSDN documentation will
have different URLs). It is *bit* 24 of lParam that carries that
meaning. lParam is a simple 32-bit value, not a pointer to a structure.

> Does anyone know where i can find the structure definitions for the key and
> mouse messages, or can anyone tell me what they are.

You already have the MSDN documentation that tells you all you need.
Where a message refers to a structure, the documentation page will link
to the appropriate structure (as with your WM_CREATE example). Where it
doesn't, it doesn't.

> Thanks in advance
> Neil
[quoted text clipped - 39 lines]
> >> Thanks in advance
> >> Neil

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Chris Dunaway - 31 Oct 2005 18:39 GMT

> lParam is a simple 32-bit value, not a pointer to a structure.

Not according to this doc:

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/winui/winui/win
dowsuserinterface/windowing/windows/windowreference/windowmessages/wm_create.asp

<QUOTE>
Parameters

wParam
This parameter is not used.
lParam
Pointer to a CREATESTRUCT structure that contains information
about the window being created.
</QUOTE>

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