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SiteMap Class

Definition

The SiteMap class is an in-memory representation of the navigation structure for a site, which is provided by one or more site map providers. This class cannot be inherited.

public ref class SiteMap abstract sealed
public static class SiteMap
type SiteMap = class
Public Class SiteMap
Inheritance
SiteMap

Examples

This section contains two code examples. The first code example demonstrates how to declare a site map provider in a Web.config file. The second code example demonstrates how to use a SiteMap object.

The following code example is a Web.config configuration section that demonstrates how an XmlSiteMapProvider object is declared as the default SiteMapProvider object.

<siteMap defaultProvider="MyXmlSiteMapProvider" enabled="true">  
  <providers>  
    <add name="MyXmlSiteMapProvider"  
      description="The site map provider that reads in the .sitemap XML files."  
      type="System.Web.XmlSiteMapProvider, System.Web, Version=2.0.3600.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a"  
      siteMapFile="my.sitemap" />  
  </providers>  
</siteMap>  

The following code example demonstrates how to use the SiteMap object by accessing its static members to display information about the RootNode and CurrentNode properties. Compare it to the output that is rendered by the SiteMapPath control.

<%@ Page language="c#"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
private void Page_Load(object sender, System.EventArgs e)
{
    // Examine the CurrentNode, and navigate the SiteMap relative to it.
    Response.Write(SiteMap.CurrentNode.Title + "<br />");
    Response.Write("<font COLOR='red'>" + SiteMap.CurrentNode.Url + "</font><br />");

    // What nodes are children of the CurrentNode?
    if (SiteMap.CurrentNode.HasChildNodes) {
        IEnumerator childNodesEnumerator = SiteMap.CurrentNode.ChildNodes.GetEnumerator();
        while (childNodesEnumerator.MoveNext()) {
            // Prints the Title of each node.
            Response.Write(childNodesEnumerator.Current.ToString() + "<br />");
        }
    }
    Response.Write("<hr />");

    // Examine the RootNode, and navigate the SiteMap relative to it.
    Response.Write(SiteMap.RootNode.Title + "<br />");
    Response.Write(SiteMap.RootNode.Url + "<br />");

    // What nodes are children of the RootNode?
    if (SiteMap.RootNode.HasChildNodes) {
        IEnumerator rootNodesChildrenEnumerator = SiteMap.RootNode.ChildNodes.GetEnumerator();
        while (rootNodesChildrenEnumerator.MoveNext()) {
            // Prints the Title of each node.
            Response.Write(rootNodesChildrenEnumerator.Current.ToString() + "<br />");
        }
    }

}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>ASP.NET Example</title>
</head>
<body>
    <form id="Form1" runat="server">
      <asp:SiteMapPath
          runat="server"
        ID="SiteMapPath1"
        ShowToolTips="false"/>
    </form>
  </body>
</html>
<%@ Page language="VB"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">
Private Sub Page_Load(sender As Object, e As System.EventArgs)

  ' Examine the CurrentNode, and navigate the SiteMap relative to it.
  Response.Write(SiteMap.CurrentNode.Title & "<br />")
  Response.Write("<font COLOR='red'>" & SiteMap.CurrentNode.Url & "</font><br />")

  ' What nodes are children of the CurrentNode?
  If (SiteMap.CurrentNode.HasChildNodes) Then
      Dim childNodesEnumerator As IEnumerator = SiteMap.CurrentNode.ChildNodes.GetEnumerator()

      While (childNodesEnumerator.MoveNext())
          ' Prints the Title of each node.
          Response.Write(childNodesEnumerator.Current.ToString() & "<br />")
      End While

  End If
  Response.Write("<hr />")

  ' Examine the RootNode, and navigate the SiteMap relative to it.
  Response.Write(SiteMap.RootNode.Title & "<br />")
  Response.Write(SiteMap.RootNode.Url & "<br />")

  ' What nodes are children of the RootNode?
  If (SiteMap.RootNode.HasChildNodes) Then
      Dim rootNodesChildrenEnumerator As IEnumerator = SiteMap.RootNode.ChildNodes.GetEnumerator()
      While (rootNodesChildrenEnumerator.MoveNext())
          ' Prints the Title of each node.
          Response.Write(rootNodesChildrenEnumerator.Current.ToString() & "<br />")
      End While
  End If

End Sub ' Page_Load
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>ASP.NET Example</title>
</head>
<body>
    <form id="Form1" runat="server">
        <asp:SiteMapPath
            runat="server"
          ID="SiteMapPath1"
          ShowToolTips="false"/>

    </form>
  </body>
</html>

Remarks

Site maps are used in conjunction with the SiteMapDataSource, SiteMapPath, and other controls to render an effective navigation interface for users to navigate a Web site. A SiteMap object is a component of the ASP.NET site navigation infrastructure that provides access to read-only site map information for page and control developers using navigation and SiteMapDataSource controls. Other components of the ASP.NET site navigation infrastructure include the SiteMapProvider and XmlSiteMapProvider classes, the Web.sitemap file, and the various controls that work with the SiteMap class, such as the SiteMapPath control, to render content and menus.

The SiteMap has several functions:

  • It provides the root node of the site navigation hierarchy (there can be only one root node).

  • It identifies which site map provider is the principal, or default, provider.

  • It keeps track of all the provider objects that are used to create the SiteMap.

Fundamentally, the SiteMap is a container for a hierarchical collection of SiteMapNode objects. However, the SiteMap does not maintain the relationships between the nodes; rather, it delegates this to the site map providers. The SiteMap acts as an interface to the site navigation information (in the form of SiteMapNode objects) that is held by these site map providers. It keeps track of the providers from which it can access site navigation data and exposes its Providers collection. A provider can store its site map information in any way - as long as it extends the SiteMapProvider abstract class, the SiteMap class can be initialized successfully from it.

The default provider for the SiteMap class is the XmlSiteMapProvider class, which works with an XML configuration file, Web.sitemap. However, you can write your own SiteMapProvider object, and use it to initialize the site map for your site. For an example of a custom site map provider, see SiteMapProvider.

A default site map configuration is specified that manages the site navigation configuration. You can override this configuration in the Web.config file, should you choose to write your own site map provider.

The SiteMap class offers only static members for performance and it can be accessed at any time in a given site from a Web Form or Web server control.

Properties

CurrentNode

Gets a SiteMapNode control that represents the currently requested page.

Enabled

Gets a Boolean value indicating if a site map provider is specified in the Web.config file and if the site map provider is enabled.

Provider

Gets the default SiteMapProvider object for the current site map.

Providers

Gets a read-only collection of named SiteMapProvider objects that are available to the SiteMap class.

RootNode

Gets a SiteMapNode object that represents the top-level page of the navigation structure for the site.

Events

SiteMapResolve

Occurs when the CurrentNode property is accessed.

Applies to

See also