1、 afterFilter(), executed after all controller logic, including the rendering of the view
2、 beforeFilter(), executed before any controller action logic
3、 beforeRender(), executed after controller logic, but before the view is rendered

afterFilter(),all controller（包括渲染view） 以后执行，

beforeFilter(),any controller 以前执行

beforeRender(),controller以后，渲染view以前，执行