Occurs before page initialization.
Assembly: System.Web (in System.Web.dll)
This event enables you to check conditions of the page request, such as whether the page is being loaded in response to a postback. You can also check the values of profile properties.
The event enables you to set values that are used later in the page life cycle. You can dynamically set a master page or a theme for the requested page, and create dynamic controls.
For more information about how the event fits into the ASP.NET life cycle, see ASP.NET Page Life Cycle Overview.
Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.