By default, the Checked property is 0 ( unchecked ). The Checked property specifies the state of the element's check box. Use the ShowCheckBox property to show or hide the element's checkbox. The CheckElement event occurs once the state of the element's checkbox is changed. Use the CheckBoxAlign property to align the element's checkbox. The Background( exCheckBoxState0) Specifies the visual appearance for the check box in 0 state. The Background(exCheckBoxState1) Specifies the visual appearance for the check box in 1 state.