Name
MSG
Synopsis
Contains all information that defines a Windows message:
Public Type MSG hwnd As Long message As Long wParam As Long lParam As Long time As Long pt As POINTAPI End Type
Structure Members
-
hwnd
The handle of the window to which the message is directed.
-
message
The message to be passed to this window. All window messages are constants and are defined in the Win32 Software Development Kit (SDK) header files. The header files WINUSER.H and WINABLE.H contain most of these constants.
-
wParam
andlParam
Many messages use the
wParam
andlParam
elements to pass extra information to the receiving window procedure. This extra information depends on the message. For example, it could indicate which mouse button was pressed, or if the Ctrl key was pressed in combination with the currently pressed key. Some messages need to pass much more information than is possible with thewParam
andlParam
arguments. To get around this limitation, some messages have special structures associated with them. Pointers to these structures are passed in either thelParam
or thewParam
elements.Each message has its own identity -- that is, the way one message fills in the
MSG
structure is not the way every message will fill it in. Most messages have their own information that must be passed on to the receiving window. Therefore, become familiar with the message that you are going to be trapping before you write the code or you might be in for a surprise.-
time
Represents when the message was posted. ...
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