The TB_GETSTATE message retrieves information about the state of the specified button in a toolbar, such as whether it is enabled, pressed, or checked.
TB_GETSTATE
wParam = (WPARAM) idButton;
lParam = 0;
Parameters
idButton
Command identifier of the button for which to retrieve information.
Return Values
Returns the button state information if successful or - 1 otherwise. The button state information can be a combination of the values listed in Button States.