Base class:
Load the inherited page first, and then load your own. If there is an inherited page, load the inherited page first.
Controls:
1) The init event is triggered from the innermost control (including the user control and common control) to the outermost control (page, load, prerender, and other events are triggered from the outermost control to the innermost control;
2) The execution sequence of the same events between controls depends on the control's position on the page from left to right, from top to bottom.
Note:
1) Remember that the user control is also regarded as a control in the page;
2) using a user control as a special page, the user control itself and its contained controls follow the same rules;
3) sometimes on the clientProgram(For example, JavaScript), the onload event of the client body object is used. Note that this client event is the final execution, that is, it is executed only after all the events on the server end are executed.
Address: http://www.cnblogs.com/mytechblog/articles/1803324.html