public class DynamicSiteMapProvider : StaticSiteMapProvider
{
public DynamicSiteMapProvider() : base()
{
}
private String _siteMapFileName;
private SiteMapNode _rootNode = null;
// Return the root node of the current site map.
public override SiteMapNode RootNode
{
get
{
return BuildSiteMap();
}
}
/// <summary>
/// Pull out the filename of the site map xml.
/// </summary>
/// <param name="name"></param>
/// <param name="attributes"></param>
public override void Initialize(string name, System.Collections.Specialized.NameValueCollection attributes)
{
base.Initialize(name, attributes);
_siteMapFileName = attributes["siteMapFile"];
}
private const String SiteMapNodeName = "siteMapNode";
public override SiteMapNode BuildSiteMap()
{
lock (this)
{
if (null == _rootNode)
{
Clear();
// Load the sitemap's xml from the file.
XmlDocument siteMapXml = LoadSiteMapXml();
// Create the first site map item from the top node in the xml.
XmlElement rootElement =
(XmlElement)siteMapXml.GetElementsByTagName(
SiteMapNodeName)[0];
// This is the key method - add the dynamic nodes to the xml
AddDynamicNodes(rootElement);
// Now build up the site map structure from the xml
GenerateSiteMapNodes(rootElement);
}
}
return _rootNode;
}
/// <summary>
/// Open the site map file as an xml document.
/// </summary>
/// <returns>The contents of the site map file.</returns>
private XmlDocument LoadSiteMapXml()
{
XmlDocument siteMapXml = new XmlDocument();
siteMapXml.Load(AppDomain.CurrentDomain.BaseDirect ory + _siteMapFileName);
return siteMapXml;
}
/// <summary>
/// Creates the site map nodes from the root of
/// the xml document.
/// </summary>
/// <param name="rootElement">The top-level sitemap element from the XmlDocument loaded with the site map xml.</param>
private void GenerateSiteMapNodes(XmlElement rootElement)
{
_rootNode = GetSiteMapNodeFromElement(rootElement);
AddNode(_rootNode);
CreateChildNodes(rootElement, _rootNode);
}
/// <summary>
/// Recursive method! This finds all the site map elements
/// under the current element, and creates a SiteMapNode for
/// them. On each of these, it calls this method again to
/// create it's new children, and so on.
/// </summary>
/// <param name="parentElement">The xml element to iterate through.</param>
/// <param name="parentNode">The site map node to add the new children to.</param>
private void CreateChildNodes(XmlElement parentElement, SiteMapNode parentNode)
{
foreach (XmlNode xmlElement in parentElement.ChildNodes)
{
if (xmlElement.Name == SiteMapNodeName)
{
SiteMapNode childNode = GetSiteMapNodeFromElement((XmlElement)xmlElement);
AddNode(childNode, parentNode);
CreateChildNodes((XmlElement)xmlElement, childNode);
}
}
}
/// <summary>
/// The key method. You can add your own code in here
/// to add xml nodes to the structure, from a
/// database, file on disk, or just from code.
/// To keep the example short, I'm just adding from code.
/// </summary>
/// <param name="rootElement"></param>
private void AddDynamicNodes(XmlElement rootElement)
{
// Add some football teams
XmlElement teams = AddDynamicChildElement(rootElement, "", "Football Teams", "List of football teams created dynamically");
AddDynamicChildElement(teams, "~/teams.aspx?name=Watford", "Watford", "Watford's team details");
AddDynamicChildElement(teams, "~/teams.aspx?name=Reading", "Reading", "Reading's team details");
AddDynamicChildElement(teams, "~/teams.aspx?name=Liverpool", "Liverpool", "Liverpool's team details");
XmlElement sheffield = AddDynamicChildElement(teams, "", "Sheffield", "There is more than one team in Sheffield");
AddDynamicChildElement(sheffield, "~/teams.aspx?name=SheffieldUnited", "Sheffield United", "Sheffield United's team details");
AddDynamicChildElement(sheffield, "~/teams.aspx?name=SheffieldWednesday", "Sheffield Wednesday", "Sheffield Wednesday's team details");
XmlElement manchester = AddDynamicChildElement(teams, "", "Manchester", "There is more than one team in Manchester");
AddDynamicChildElement(manchester, "~/teams.aspx?name=ManchesterUnited", "Manchester United", "Manchester United's team details");
AddDynamicChildElement(manchester, "~/teams.aspx?name=ManchesterCity", "Manchester City", "Manchester City's team details");
}
private static XmlElement AddDynamicChildElement(XmlElement parentElement, String url, String title, String description)
{
// Create new element from the parameters
XmlElement childElement = parentElement.OwnerDocument.CreateElement(SiteMapN odeName);
childElement.SetAttribute("url", url);
childElement.SetAttribute("title", title);
childElement.SetAttribute("description", description);
// Add it to the parent
parentElement.AppendChild(childElement);
return childElement;
}
private SiteMapNode GetSiteMapNodeFromElement(XmlElement rootElement)
{
SiteMapNode newSiteMapNode;
String url = rootElement.GetAttribute("url");
String title = rootElement.GetAttribute("title");
String description = rootElement.GetAttribute("description");
// The key needs to be unique, so hash the url and title.
newSiteMapNode = new SiteMapNode(this,
(url + title).GetHashCode().ToString(), url, title, description);
return newSiteMapNode;
}
protected override SiteMapNode GetRootNodeCore()
{
return RootNode;
}
// Empty out the existing items.
protected override void Clear()
{
lock (this)
{
_rootNode = null;
base.Clear();
}
}
}