Retrieves information about the state of the specified button in a toolbar control, such as whether it is enabled, pressed, or checked.
The button state information if successful or – 1 otherwise. The button state information can be a combination of the values listed in CToolBarCtrl::AddButtons.
This function is especially handy if you want to retrieve more than one of the button states. To just retrieve one state, use one of the following member functions: IsButtonEnabled, IsButtonChecked, IsButtonPressed, IsButtonHidden, or IsButtonIndeterminate. However, the GetState member function is the only way to detect the TBSTATE_WRAP button state.