IHierarchyData Interfaccia

Definizione

Espone un nodo di una struttura di dati gerarchica, incluso l'oggetto nodo e alcune proprietà che descrivono le caratteristiche del nodo.Exposes a node of a hierarchical data structure, including the node object and some properties that describe characteristics of the node. Gli oggetti che implementano l'interfaccia IHierarchyData possono essere inclusi in insiemi IHierarchicalEnumerable e vengono utilizzati da controlli di navigazione nel sito e di origine dati di ASP.NET.Objects that implement the IHierarchyData interface can be contained in IHierarchicalEnumerable collections, and are used by ASP.NET site navigation and data source controls.

public interface class IHierarchyData
public interface IHierarchyData
type IHierarchyData = interface
Public Interface IHierarchyData
Derivato

Esempi

Nell'esempio di codice seguente viene illustrato come implementare IHierarchyData l'interfaccia con una classe che esegue il FileSystemInfo wrapping di un oggetto.The following code example demonstrates how to implement the IHierarchyData interface with a class that wraps a FileSystemInfo object. La FileSystemInfo classe è un valido esempio di nodo di dati gerarchico, rappresentato dall' IHierarchyData interfaccia per i controlli di origine dati gerarchici ASP.NET.The FileSystemInfo class is a good example of a hierarchical data node, which the IHierarchyData interface represents for ASP.NET hierarchical data source controls. Questo esempio di codice fa parte di un esempio più ampio fornito HierarchicalDataSourceControl per la classe.This code example is part of a larger example provided for the HierarchicalDataSourceControl class.

public class FileSystemHierarchyData : IHierarchyData
{
    private FileSystemInfo fileSystemObject = null;

    public FileSystemHierarchyData(FileSystemInfo obj)
    {
        fileSystemObject = obj;
    }

    public override string ToString()
    {
        return fileSystemObject.Name;
    }
    // IHierarchyData implementation.
    public bool HasChildren
    {
        get
        {
            if (typeof(DirectoryInfo) == fileSystemObject.GetType())
            {
                DirectoryInfo temp = (DirectoryInfo)fileSystemObject;
                return (temp.GetFileSystemInfos().Length > 0);
            }
            else return false;
        }
    }
    // DirectoryInfo returns the OriginalPath, while FileInfo returns
    // a fully qualified path.
    public string Path
    {
        get
        {
            return fileSystemObject.ToString();
        }
    }
    public object Item
    {
        get
        {
            return fileSystemObject;
        }
    }
    public string Type
    {
        get
        {
            return "FileSystemData";
        }
    }
    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 Class FileSystemHierarchyData
    Implements IHierarchyData

    Public Sub New(ByVal obj As FileSystemInfo)
        fileSystemObject = obj
    End Sub

    Private fileSystemObject As FileSystemInfo = Nothing

    Public Overrides Function ToString() As String
        Return fileSystemObject.Name
    End Function

    ' IHierarchyData implementation.
    Public Overridable ReadOnly Property HasChildren() As Boolean _
     Implements IHierarchyData.HasChildren
        Get
            If GetType(DirectoryInfo) Is fileSystemObject.GetType() Then
                Dim temp As DirectoryInfo = _
                    CType(fileSystemObject, DirectoryInfo)
                Return temp.GetFileSystemInfos().Length > 0
            Else
                Return False
            End If
        End Get
    End Property
    ' DirectoryInfo returns the OriginalPath, while FileInfo returns
    ' a fully qualified path.

    Public Overridable ReadOnly Property Path() As String _
     Implements IHierarchyData.Path
        Get
            Return fileSystemObject.ToString()
        End Get
    End Property

    Public Overridable ReadOnly Property Item() As Object _
     Implements IHierarchyData.Item
        Get
            Return fileSystemObject
        End Get
    End Property

    Public Overridable ReadOnly Property Type() As String _
     Implements IHierarchyData.Type
        Get
            Return "FileSystemData"
        End Get
    End Property

    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

Nell'esempio di codice seguente viene illustrato come scorrere in modo ricorsivo una IHierarchicalEnumerable raccolta, estrarre l' IHierarchyData elemento dall'enumeratore GetHierarchyData utilizzando il metodo ed eseguire operazioni di base con l'elemento di dati.The following code example demonstrates how to recursively iterate through an IHierarchicalEnumerable collection, extract the IHierarchyData item from the enumerator using the GetHierarchyData method, and perform basic work with the data item.

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="ihd_1.aspx.cs" Inherits="ihd_1_aspx" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Untitled Page</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    
    </div>
    </form>
</body>
</html>
<%@ Page Language="VB" AutoEventWireup="true" CodeFile="ihd_1.aspx.vb" Inherits="ihd_1_aspx" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Untitled Page</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    
    </div>
    </form>
</body>
</html>

Commenti

L' IHierarchyData interfaccia viene implementata dalle classi che rappresentano i nodi di una struttura gerarchica e tiene traccia delle relazioni gerarchiche con i relativi nodi padre e figlio.The IHierarchyData interface is implemented by classes that represent nodes of a hierarchical structure, and track the hierarchical relationships to their parent and child nodes. Le classi che implementano l' IHierarchyData interfaccia possono essere contenute in raccolte che implementano l' IHierarchicalEnumerable interfaccia.Classes that implement the IHierarchyData interface can be contained in collections that implement the IHierarchicalEnumerable interface.

Proprietà

HasChildren

Indica se al nodo di dati gerarchico rappresentato dall'oggetto IHierarchyData sono associati nodi figlio.Indicates whether the hierarchical data node that the IHierarchyData object represents has any child nodes.

Item

Ottiene il nodo di dati gerarchico rappresentato dall'oggetto IHierarchyData.Gets the hierarchical data node that the IHierarchyData object represents.

Path

Ottiene il percorso gerarchico del nodo.Gets the hierarchical path of the node.

Type

Ottiene il nome del tipo di classe Object disponibile nella proprietà Item.Gets the name of the type of Object contained in the Item property.

Metodi

GetChildren()

Ottiene un oggetto di enumerazione che rappresenta tutti i nodi figlio del nodo gerarchico corrente.Gets an enumeration object that represents all the child nodes of the current hierarchical node.

GetParent()

Ottiene un oggetto IHierarchyData che rappresenta il nodo padre del nodo gerarchico corrente.Gets an IHierarchyData object that represents the parent node of the current hierarchical node.

Si applica a

Vedi anche