[MenuItem("CONTEXT/Transform/hello")]
public static void Hello(MenuCommand cmd){
Transform tran = cmd.context as Transform;
tran.position = tran.position * 2;
}组件菜单扩展指定是在Inspector页面右键组件后显示的菜单
命名模式:CONTEXT/组件类名/菜单名
通过MenuCommand的context变量获取到要操作的组件