Imports Microsoft.VisualBasic
Imports System
Imports System.Data
Imports System.Collections
Imports System.Security.Permissions
Imports System.Web
Imports System.Web.Hosting
Namespace Samples.AspNet.VB
<AspNetHostingPermission(SecurityAction.Demand, Level:=AspNetHostingPermissionLevel.Minimal), _
AspNetHostingPermission(SecurityAction.InheritanceDemand, level:=AspNetHostingPermissionLevel.Minimal)> _
Public Class SampleVirtualDirectory
Inherits VirtualDirectory
Private spp As SamplePathProvider
' Declare the variable the property uses.
Private existsValue As Boolean
Public ReadOnly Property exists() As Boolean
Get
Return existsValue
End Get
End Property
Public Sub New(ByVal virtualDir As String, ByVal provider As SamplePathProvider)
MyBase.New(virtualDir)
spp = provider
GetData()
End Sub
Protected Sub GetData()
' Get the data from the SamplePathProvider.
Dim spp As SamplePathProvider
spp = CType(HostingEnvironment.VirtualPathProvider, SamplePathProvider)
Dim ds As DataSet
ds = spp.GetVirtualData
' Clean up the path to match data in resource file.
Dim path As String
path = VirtualPath.Replace(HostingEnvironment.ApplicationVirtualPath, "")
Dim trimChars() As Char = {"/"c}
path = path.TrimEnd(trimChars)
' Get the virtual directory from the resource table.
Dim dirs As DataTable
dirs = ds.Tables("resource")
Dim rows As DataRow()
rows = dirs.Select( _
String.Format("(name = '{0}') AND (type='dir')", path))
' If the select returned a row, the directory exits.
If (rows.Length > 0) Then
existsValue = True
' Get the children from the resource table.
' This technique works for small numbers of virtual resources.
' Sites with moderate to large numbers of virtual
' resources should choose a method that consumes fewer
' computer resources.
Dim childRows As DataRow()
childRows = dirs.Select( _
String.Format("parentPath = '{0}'", path))
For Each childRow As DataRow In childRows
Dim childPath As String
childPath = CType(childRow("path"), String)
If (childRow("type").ToString = "dir") Then
Dim svd As New SampleVirtualDirectory(childPath, spp)
childrenValue.Add(svd)
directoriesValue.Add(svd)
Else
Dim svf As New SampleVirtualFile(childPath, spp)
childrenValue.Add(svf)
directoriesValue.Add(svf)
End If
Next
End If
End Sub
Private childrenValue As ArrayList
Public Overrides ReadOnly Property Children() As System.Collections.IEnumerable
Get
Return childrenValue
End Get
End Property
Private directoriesValue As ArrayList
Public Overrides ReadOnly Property Directories() As System.Collections.IEnumerable
Get
Return directoriesValue
End Get
End Property
Private filesValue As ArrayList
Public Overrides ReadOnly Property Files() As System.Collections.IEnumerable
Get
Return filesValue
End Get
End Property
End Class
End Namespace