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HierarchicalDataSourceControl.GetHierarchicalView(String) Method

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Definition

Namespace:
System.Web.UI
Assembly:
System.Web.dll

Gets the view helper object for the IHierarchicalDataSource interface for the specified path.

protected:
 abstract System::Web::UI::HierarchicalDataSourceView ^ GetHierarchicalView(System::String ^ viewPath);
protected abstract System.Web.UI.HierarchicalDataSourceView GetHierarchicalView (string viewPath);
abstract member GetHierarchicalView : string -> System.Web.UI.HierarchicalDataSourceView
Protected MustOverride Function GetHierarchicalView (viewPath As String) As HierarchicalDataSourceView

Parameters

viewPath
String

The hierarchical path of the view to retrieve.

Returns

HierarchicalDataSourceView

A HierarchicalDataSourceView that represents a single view of the data at the hierarchical level identified by the viewPath parameter.

Examples

The following code example demonstrates how to override the GetHierarchicalView method in a class that extends the HierarchicalDataSourceControl class to return a strongly typed HierarchicalDataSourceView object. This code example is part of a larger example provided for the HierarchicalDataSourceControl class.

using System;
using System.Collections;
using System.IO;
using System.Runtime.InteropServices;
using System.Security.Permissions;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

public class FileSystemDataSource :
    HierarchicalDataSourceControl, IHierarchicalDataSource
{
    private FileSystemDataSourceView view = null;

    public FileSystemDataSource() : base() { }

    protected override HierarchicalDataSourceView
        GetHierarchicalView(string viewPath)
    {
        view = new FileSystemDataSourceView(viewPath);
        return view;
    }
}

Imports System.Collections
Imports System.IO
Imports System.Runtime.InteropServices
Imports System.Security.Permissions
Imports System.Web
Imports System.Web.UI
Imports System.Web.UI.WebControls

Namespace Samples.AspNet

    Public Class FileSystemDataSource
        Inherits HierarchicalDataSourceControl

        Public Sub New()
        End Sub

        Private view As FileSystemDataSourceView = Nothing

        Protected Overrides Function GetHierarchicalView( _
            ByVal viewPath As String) As HierarchicalDataSourceView

            view = New FileSystemDataSourceView(viewPath)
            Return view
        End Function

    End Class

Remarks

This GetHierarchicalView method provides the default implementation for the HierarchicalDataSourceControl class, which simply returns null. Classes that derive from the HierarchicalDataSourceControl class override this method and provide an implementation to return a strongly typed view that derives from HierarchicalDataSourceView.

Applies to

See also