[in] Specifies the repeat count, scan code, extended-key flag, context code, previous key-state flag, and transition-state flag. For more information about the lParam parameter, see Keystroke Message Flags. This parameter can be one or more of the following values.
Specifies the repeat count. The value is the number of times the keystroke is repeated as a result of the user's holding down the key.
Specifies the scan code. The value depends on the OEM.
Specifies whether the key is an extended key, such as a function key or a key on the numeric keypad. The value is 1 if the key is an extended key; otherwise, it is 0.
Specifies the context code. The value is 1 if the ALT key is down; otherwise, it is 0.
Specifies the previous key state. The value is 1 if the key is down before the message is sent; it is 0 if the key is up.
Specifies the transition state. The value is 0 if the key is being pressed and 1 if it is being released.
in this description of what lParam will contain, how do i check to see what the transition state is?