asp.net - web.sitemap のパス検索エラー

Question

Public Class Main

Inherits StaticSiteMapProvider

Dim conn As New ConnectionVB
Dim _rootNode As SiteMapNode = Nothing
Dim _siteMapFileName As String
Dim SiteMapNodeName As String = "siteMapNode"

Public Sub DynamicSiteMapProvider()
End Sub

Public Shadows Function RootNode() As SiteMapNode
    Return BuildSiteMap()
End Function

Public Overrides Sub Initialize(name As String, attributes As NameValueCollection)
    //Me.Initialize(name, attributes)
    _siteMapFileName = attributes("siteMapFile")
End Sub

Protected Overrides Function GetRootNodeCore() As SiteMapNode
    Return RootNode()
End Function

Protected Overrides Sub clear()
    SyncLock Me
        _rootNode = Nothing
        //Me.clear()
    End SyncLock
End Sub

Public Overrides Function BuildSiteMap() As SiteMapNode
    SyncLock Me
        If _rootNode Is Nothing Then
            clear()
            Dim siteMapXml As XmlDocument = LoadSiteMapXml()
            Dim rootElement As XmlElement = CType(siteMapXml.GetElementsByTagName(SiteMapNodeName)(0), XmlElement)
            AddDynamicNodes(rootElement)
            GenerateSiteMapNodes(rootElement)
        End If
    End SyncLock
    Return _rootNode
End Function

Private Function LoadSiteMapXml() As XmlDocument
    Dim siteMapXml As XmlDocument = New XmlDocument()
    siteMapXml.Load(AppDomain.CurrentDomain.BaseDirectory + _siteMapFileName) //I got an error here
    Return siteMapXml
End Function

Protected Sub AddDynamicNodes(rootElement As XmlElement)
    Dim teams As XmlElement = AddDynamicChildElement(rootElement, "", "FootballTeams", "List of football team")
End Sub

Protected Function AddDynamicChildElement(parentElement As XmlElement, url As String, title As String, description As String) As XmlElement
    Dim childElement As XmlElement = parentElement.OwnerDocument.CreateElement(SiteMapNodeName)
    childElement.SetAttribute("url", url)
    childElement.SetAttribute("title", title)
    childElement.SetAttribute("description", description)

    parentElement.AppendChild(childElement)
    Return childElement
End Function

Protected Sub GenerateSiteMapNodes(rootElement As XmlElement)
    _rootNode = GetSiteMapNodeFromElement(rootElement)
    AddNode(_rootNode)
    CreateChildNodes(rootElement, _rootNode)
End Sub

Protected Sub CreateChildNodes(parentElement As XmlElement, parentNode As SiteMapNode)
    For Each XmlElement As XmlNode In parentElement.ChildNodes
        If XmlElement.Name = SiteMapNodeName Then
            Dim childNode As SiteMapNode = GetSiteMapNodeFromElement(CType(XmlElement, XmlElement))
            AddNode(childNode, parentNode)
            CreateChildNodes(CType(XmlElement, XmlElement), childNode)
        End If
    Next
End Sub

Protected Function GetSiteMapNodeFromElement(rootElement As XmlElement) As SiteMapNode
    Dim newSiteMapNode As SiteMapNode
    Dim url As String = rootElement.GetAttribute("url")
    Dim title As String = rootElement.GetAttribute("title")
    Dim description As String = rootElement.GetAttribute("description")

    newSiteMapNode = New SiteMapNode(Me, (url + title).GetHashCode().ToString(), url, title, description)
    Return newSiteMapNode
End Function

End Class

このコードを実行すると、パスが見つからないという例外がスローされます。

siteMapXml.Load(AppDomain.CurrentDomain.BaseDirectory + _siteMapFileName)

それがエラーをスローするコード行です。

ここにエラーがあります：

System.IO.DirectoryNotFoundException: Could not find a part of the path 'c:\Users\Julian\documents\visual studio 2012\WebSites\WebSite1\'.

そこにブレークポイントを置いてパスを確認しようとしましたが、すでに正しいパスです。

このエラーの原因がわかりません。