Assembly: System.Web (in system.web.dll)
When the LoginView controls switches views, it removes the controls from the previous template and creates new child controls from the new template. The OnViewChanging method is called before the previous controls are removed.
Use the OnViewChanging method to perform any necessary processing, such as saving control information, before the controls are removed.
Raising an event invokes the event handler through a delegate. For more information, see Raising an Event.
The OnViewChanging 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 OnViewChanging in a derived class, be sure to call the base class’s OnViewChanging method so that registered delegates receive the event.