public event EventHandler<GridRowSelectionEventArgs> SelectionChanging

Public Event SelectionChanging As EventHandler(Of GridRowSelectionEventArgs)

public:
 event EventHandler<GridRowSelectionEventArgs^>^ SelectionChanging {
	void add (EventHandler<GridRowSelectionEventArgs^>^ value);
	void remove (EventHandler<GridRowSelectionEventArgs^>^ value);
}

member SelectionChanging : IEvent<EventHandler<GridRowSelectionEventArgs>,
    GridRowSelectionEventArgs>

grid.SelectionChanging += delegate(object sender, GridRowSelectionEventArgs e)
{
    //The first row will always be selected
    if(e.Row.VisibleIndex == 0)
    {
        e.NewSelectionState = true;
    }

    //The second row will always be unselected
    if (e.Row.VisibleIndex == 1)
    {
        e.NewSelectionState = false;
    }
};