Assembly: System.Web (in system.web.dll)
The OnInit method performs the initialization and setup steps required to create a Page instance. In this stage of the page's life cycle, declared server controls on the page are initialized to their default state; however, the view state of each control is not yet populated. A control on the page cannot access other server controls on the page during the Page_Init phase, regardless of whether the other controls are child or parent controls. Other server controls are not guaranteed to be created and ready for access.
Raising an event invokes the event handler through a delegate. For more information, see Handling and Raising Events.
The OnInit method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.Notes to Inheritors: When overriding OnInit in a derived class, be sure to call the base class's OnInit method so that registered delegates receive the event.