SiteMapProvider.RootProvider Property
Definition
Gets the root SiteMapProvider object in the current provider hierarchy.
public:
virtual property System::Web::SiteMapProvider ^ RootProvider { System::Web::SiteMapProvider ^ get(); };
public virtual System.Web.SiteMapProvider RootProvider { get; }
member this.RootProvider : System.Web.SiteMapProvider
Public Overridable ReadOnly Property RootProvider As SiteMapProvider
Property Value
An SiteMapProvider that is the top-level site map provider in the provider hierarchy that the current provider belongs to.
Exceptions
There is a circular reference to the current site map provider.
Examples
The following code example demonstrates how to implement the RootProvider property in a class that implements the abstract SiteMapProvider class. The SimpleTextSiteMapProvider
uses simple logic to determine whether the current provider is part of a provider hierarchy. If the provider is part of a hierarchy, it uses the RootProvider property for the parent provider as its own. If the provider is not part of a hierarchy, the provider is its own root provider.
This code example is part of a larger example provided for the SiteMapProvider class.
// Implement the ParentProvider property.
public override SiteMapProvider ParentProvider
{
get
{
return parentSiteMapProvider;
}
set
{
parentSiteMapProvider = value;
}
}
// Implement the RootProvider property.
public override SiteMapProvider RootProvider
{
get
{
// If the current instance belongs to a provider hierarchy, it
// cannot be the RootProvider. Rely on the ParentProvider.
if (this.ParentProvider != null)
{
return ParentProvider.RootProvider;
}
// If the current instance does not have a ParentProvider, it is
// not a child in a hierarchy, and can be the RootProvider.
else
{
return this;
}
}
}
' Implement the ParentProvider property.
Public Overrides Property ParentProvider() As SiteMapProvider
Get
Return parentSiteMapProvider
End Get
Set(ByVal value As SiteMapProvider)
parentSiteMapProvider = Value
End Set
End Property
' Implement the RootProvider property.
Public Overrides ReadOnly Property RootProvider() As SiteMapProvider
Get
' If the current instance belongs to a provider hierarchy, it
' cannot be the RootProvider. Rely on the ParentProvider.
If Not (Me.ParentProvider Is Nothing) Then
Return ParentProvider.RootProvider
' If the current instance does not have a ParentProvider, it is
' not a child in a hierarchy, and can be the RootProvider.
Else
Return Me
End If
End Get
End Property
Remarks
All classes that implement the SiteMapProvider class can support the concept of a site map provider hierarchy. Any hierarchical relationships between providers are maintained outside the scope of a SiteMapProviderCollection collection by the providers themselves. For an example of a functional provider hierarchy, see XmlSiteMapProvider.