Gets a string representing a lookup key for a site map node.
Assembly: System.Web (in System.Web.dll)
Internally, site navigation classes can use this lookup key when searching for site map nodes, as well as for establishing relationships between nodes. The SiteMapProvider class also exposes the FindSiteMapNodeFromKey method as a means for getting a reference to a SiteMapNode object that matches the key value.
The specific value that is used for the key is provider specific; however, it is guaranteed to not be null.