ISimpleFrameSite::PreMessageFilter
Provides a
site with the opportunity to process a message that is received by a control s own window before the control itself does any
processing.
HRESULT
PreMessageFilter(
|
HWND hWnd , |
//Handle of
window receiving message |
|
UINT msg , |
//Received message |
|
WPARAM wp , |
//WPARAM of message |
|
LPARAM lp , |
//LPARAM of message |
|
LRESULT* plResult , |
//Pointer to variable to receive result of message
processing |
|
DWORD* pdwCookie |
//Pointer to a variable used later |
|
); |
|
Parameters
hWnd
[in] Handle
of the control window receiving the message.
msg
[in] Message
received by the simple frame site.
wp
[in] The WPARAM
of the message.
lp
[in] The LPARAM
of the message.
plResult
[out] Pointer
to the address of the result variable to receive the result of the message
processing.
pdwCookie
[out] Pointer
to the DWORD variable that will be passed to PostMessageFilter if
it is called later. This parameter should only contain allocated data if this
method returns S_OK so it will also receive a call to PostMessageFilter
which can free the allocation. The caller is not in any way responsible for
anything returned in this parameter.
Return Values
S_OK
The simple
frame site will not use the message in this filter so more processing can take
place.
S_FALSE
The site has
processed the message and no further processing should occur.
E_NOTIMPL
The site does
not do any message filtering, indicating that PostMessageFilter need not
be called later.
E_POINTER
The addresses
in plResultor pdwCookie are not valid.
Remarks
Successful
return values indicate whether the site wishes to allow further processing.
S_OK indicates further processing, whereas S_FALSE means do not process
further. S_OK also indicates that the control must later call ISimpleFrameSite::PostMessageFilter.
See Also