SiteMapProvider.GetParentNode(SiteMapNode) Metode

Definisi

Ruang nama:

System.Web

Rakitan:

System.Web.dll

Saat ditimpa di kelas turunan, mengambil simpul induk dari objek tertentu SiteMapNode .

public:
 abstract System::Web::SiteMapNode ^ GetParentNode(System::Web::SiteMapNode ^ node);

public abstract System.Web.SiteMapNode GetParentNode(System.Web.SiteMapNode node);

abstract member GetParentNode : System.Web.SiteMapNode -> System.Web.SiteMapNode

Public MustOverride Function GetParentNode (node As SiteMapNode) As SiteMapNode

Parameter

node

SiteMapNode

SiteMapNode yang akan diambil node induknya.

Mengembalikan

SiteMapNode

SiteMapNode Yang mewakili induk node; jika tidak, null, jika SiteMapNode tidak memiliki induk atau pemangkasan keamanan diaktifkan dan simpul induk tidak dapat diakses oleh pengguna saat ini.

Catatan: GetParentNode(SiteMapNode) mungkin juga mengembalikan null jika simpul induk milik penyedia yang berbeda. Dalam hal ini, gunakan ParentNode properti sebagai node gantinya.

Contoh

Contoh kode berikut menunjukkan cara mengimplementasikan GetParentNode metode di kelas yang mengimplementasikan kelas abstrak SiteMapProvider . Menyimpan SimpleTextSiteMapProvider hubungan induk/anak hierarkis antara SiteMapNode objek dalam IList antarmuka, seperti ArrayList objek.

Contoh kode ini adalah bagian dari contoh yang lebih besar yang disediakan untuk SiteMapProvider kelas .

// Implement the GetChildNodes method.
public override SiteMapNodeCollection GetChildNodes(SiteMapNode node)
{
  SiteMapNodeCollection children = new SiteMapNodeCollection();
  // Iterate through the ArrayList and find all nodes that have the specified node as a parent.
  lock (this)
  {
    for (int i = 0; i < childParentRelationship.Count; i++)
    {

      string nodeUrl = ((DictionaryEntry)childParentRelationship[i]).Key as string;

      SiteMapNode parent = GetNode(childParentRelationship, nodeUrl);

      if (parent != null && node.Url == parent.Url)
      {
        // The SiteMapNode with the Url that corresponds to nodeUrl
        // is a child of the specified node. Get the SiteMapNode for
        // the nodeUrl.
        SiteMapNode child = FindSiteMapNode(nodeUrl);
        if (child != null)
        {
          children.Add(child as SiteMapNode);
        }
        else
        {
          throw new Exception("ArrayLists not in sync.");
        }
      }
    }
  }
  return children;
}
protected override SiteMapNode GetRootNodeCore()
{
  return RootNode;
}
// Implement the GetParentNode method.
public override SiteMapNode GetParentNode(SiteMapNode node)
{
  // Check the childParentRelationship table and find the parent of the current node.
  // If there is no parent, the current node is the RootNode.
  SiteMapNode parent = null;
  lock (this)
  {
    // Get the Value of the node in childParentRelationship
    parent = GetNode(childParentRelationship, node.Url);
  }
  return parent;
}

' Implement the GetChildNodes method.
Public Overrides Function GetChildNodes(ByVal node As SiteMapNode) As SiteMapNodeCollection
  Dim children As New SiteMapNodeCollection()
  ' Iterate through the ArrayList and find all nodes that have the specified node as a parent.
  SyncLock Me
    Dim i As Integer
    For i = 0 To childParentRelationship.Count - 1

      Dim de As DictionaryEntry = CType(childParentRelationship(i), DictionaryEntry)
      Dim nodeUrl As String = CType(de.Key, String)

      Dim parent As SiteMapNode = GetNode(childParentRelationship, nodeUrl)

      If Not (parent Is Nothing) AndAlso node.Url = parent.Url Then
        ' The SiteMapNode with the Url that corresponds to nodeUrl
        ' is a child of the specified node. Get the SiteMapNode for
        ' the nodeUrl.
        Dim child As SiteMapNode = FindSiteMapNode(nodeUrl)
        If Not (child Is Nothing) Then
          children.Add(CType(child, SiteMapNode))
        Else
          Throw New Exception("ArrayLists not in sync.")
        End If
      End If
    Next i
  End SyncLock
  Return children
End Function 'GetChildNodes

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

' Implement the GetParentNode method.
Public Overrides Function GetParentNode(ByVal node As SiteMapNode) As SiteMapNode
  ' Check the childParentRelationship table and find the parent of the current node.
  ' If there is no parent, the current node is the RootNode.
  Dim parent As SiteMapNode = Nothing
  SyncLock Me
    ' Get the Value of the node in childParentRelationship
    parent = GetNode(childParentRelationship, node.Url)
  End SyncLock
  Return parent
End Function 'GetParentNode

Lihat juga

• GetChildNodes(SiteMapNode)