class HotKeysCommands
{
private static RoutedUICommand _GroupAdd = new       RoutedUICommand();
        /// <summary>
        /// 新建分组
        /// </summary>
        public static RoutedUICommand GroupAdd
        {
            get { return HotKeysCommands._GroupAdd; }
           
        }
}

TreeViewItem treeitem=new TreeViewItem ()
ContextMenu contextGroupMenu = new ContextMenu();

MenuItem menuItem = new MenuItem();
menuItem.InputGestureText = “Alt+G+A”;
menuItem.Command = HotKeysCommands.GroupAdd

KeyBinding keybin = new KeyBinding();
CommandBinding com = new CommandBinding();
keybin.Gesture =  new KeyGesture(Key.P | Key.A,  ModifierKeys.Control);
keybin.Command = HotKeysCommands.GroupAdd;
com.Command =  HotKeysCommands.GroupAdd;

treeitem.InputBindings.Add(keybin);
treeitem.CommandBindings.Add(HotKeysCommands.GroupAdd);
contextGroupMenu.items.add(menuItem );
treeitem.ContextMenu=contextGroupMenu ;