SiteMapProviderCollection.Add Method (ProviderBase)
Assembly: System.Web (in system.web.dll)
The Name of the SiteMapProvider is a null reference (Nothing in Visual Basic).
provider is not an instance of the SiteMapProvider class.
- or -
A SiteMapProvider with the same name already exists in the SiteMapProviderCollection.
The SiteMapProviderCollection is read-only.
The SiteMapProviderCollection object that is returned by the Providers property is read-only. For this reason, you cannot use the Add and AddArray methods to add additional providers programmatically at run time. Therefore, the Add and AddArray methods are used only in scenarios where you manually create site map provider objects and manage them with an instance of the SiteMapProviderCollection class. The Add(ProviderBase) method checks the type of the specified provider, and then calls the Add(SiteMapProvider) method to add it to the collection.
Because the SiteMap class is static, any SiteMapProvider contained in its Providers collection remains for the lifetime of the Web application.
Windows 98, Windows 2000 SP4, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.