IHierarchyData.GetParent 方法

public:
 System::Web::UI::IHierarchyData ^ GetParent();

public System.Web.UI.IHierarchyData GetParent();

abstract member GetParent : unit -> System.Web.UI.IHierarchyData

Public Function GetParent () As IHierarchyData

傳回

一個 IHierarchyData 代表當前階層節點父節點的物件。

範例

以下程式碼範例示範如何在實作GetParent介面的類別中實作該IHierarchyData方法。 類別 FileSystemHierarchyData 會包裹物件 FileSystemInfo ，方法實 GetParent 作會檢查物件 FileSystemInfo 的型別，並根據該類型回傳適當的父物件。 此程式碼範例是為介面與IHierarchyData類別提供HierarchicalDataSourceControl較大範例的一部分。

public IHierarchicalEnumerable GetChildren()
{
    FileSystemHierarchicalEnumerable children =
        new FileSystemHierarchicalEnumerable();

    if (typeof(DirectoryInfo) == fileSystemObject.GetType())
    {
        DirectoryInfo temp = (DirectoryInfo)fileSystemObject;
        foreach (FileSystemInfo fsi in temp.GetFileSystemInfos())
        {
            children.Add(new FileSystemHierarchyData(fsi));
        }
    }
    return children;
}

public IHierarchyData GetParent()
{
    FileSystemHierarchicalEnumerable parentContainer =
        new FileSystemHierarchicalEnumerable();

    if (typeof(DirectoryInfo) == fileSystemObject.GetType())
    {
        DirectoryInfo temp = (DirectoryInfo)fileSystemObject;
        return new FileSystemHierarchyData(temp.Parent);
    }
    else if (typeof(FileInfo) == fileSystemObject.GetType())
    {
        FileInfo temp = (FileInfo)fileSystemObject;
        return new FileSystemHierarchyData(temp.Directory);
    }
    // If FileSystemObj is any other kind of FileSystemInfo, ignore it.
    return null;
}

    Public Overridable Function GetChildren() _
        As IHierarchicalEnumerable _
        Implements IHierarchyData.GetChildren

        Dim children As New FileSystemHierarchicalEnumerable()

        If GetType(DirectoryInfo) Is fileSystemObject.GetType() Then
            Dim temp As DirectoryInfo = _
                CType(fileSystemObject, DirectoryInfo)
            Dim fsi As FileSystemInfo
            For Each fsi In temp.GetFileSystemInfos()
                children.Add(New FileSystemHierarchyData(fsi))
            Next fsi
        End If
        Return children
    End Function 'GetChildren


    Public Overridable Function GetParent() As IHierarchyData _
     Implements IHierarchyData.GetParent
        Dim parentContainer As New FileSystemHierarchicalEnumerable()

        If GetType(DirectoryInfo) Is fileSystemObject.GetType() Then
            Dim temp As DirectoryInfo = _
                CType(fileSystemObject, DirectoryInfo)
            Return New FileSystemHierarchyData(temp.Parent)
        ElseIf GetType(FileInfo) Is fileSystemObject.GetType() Then
            Dim temp As FileInfo = CType(fileSystemObject, FileInfo)
            Return New FileSystemHierarchyData(temp.Directory)
        End If
        ' If FileSystemObj is any other kind of FileSystemInfo, ignore it.
        Return Nothing
    End Function 'GetParent
End Class

備註

該IHierarchyData介面未定義 HasParent 便利性，因此呼叫者必須檢查方法的GetParent回傳值null，以判斷當前IHierarchyData節點是否為該節點所屬階層式資料結構的根節點。

另請參閱

• GetChildren()
• HasChildren