1.Content Page PreInit Event
2.Page:UserControl Init Event
3.Master:UserControl Init Event
4.Master Page Init Event
5.Content Page Init Event
6.Content Page Load Event
7.Master Page Load Event
8.Page:UserControl Load Event
9.Master:UserControl Load Event
10.Content page prerender
11.Master Page's Page_prerender
12.Master Page's Page_Unload
13.and finally Content page's Page_Unload
