When set, the MovePreviousItem property generates the Click event handler for the Move Previous button. This event handler calls the MovePrevious method when the Move Previous button is clicked at run time.
This property is null if it was not previously set and it is accessed before the AddStandardItems method is implicitly or explicitly called.
The BindingNavigator control will disable the Move Previous button under the following run-time circumstances: the BindingSource property is null or the Position property is less than or equal to 0.
In the default implementation, this property represents a control of type ToolStripButton.