invalid cast CustomPrincipal

[Polar Bear]

Hi,

 

I think I read all of the information in the whole internet regarding the CustomPrincipal class. I have every tutotorial and reference that I could find about inplemending this, and all show the same code. A lot of people like myself are having problems when trying to cast the HttpContext.User to the CustomPrincipal Class. Maybe someone here has an answer.

 

 

Default.aspx

<%@ Import Namespace="System.Web.Security" %>
<%@ Import Namespace="System.Security.Principal" %>
<%@ Assembly Src="CustomPrincipal.vb" %>

Sub Page_Load
If Not IsPostBack Then

End If

'Dim cp As CustomPrincipal = CType(HttpContext.Current.User, CustomPrincipal) ' gives invalid cast error

lblMessage.Text = "User: " & HttpContext.Current.User.Identity.Name ' should be cp.Identity.Name

End Sub

 

Global.asax

 

 
<%@ Import Namespace="System.Web.Security" %>
<%@ Import Namespace="System.Security.Principal" %>
<%@ Assembly Src="CustomPrincipal.vb" %>
<script language="VB" runat="server">
Sub Application_AuthenticationRequest(sender As Object, e As EventArgs)
' Extract the forms authentication cookie
Dim cookieName As String = FormsAuthentication.FormsCookieName
Dim authCookie As HttpCookie = Context.Request.Cookies(cookieName)

If (authCookie Is Nothing) Then
' There is no authentication cookie
'Return
End If

Dim authTicket As FormsAuthenticationTicket = Nothing

Try
authTicket = FormsAuthentication.Decrypt(authCookie.Value)
Catch ex As Exception
'Return
End Try

If (authTicket Is Nothing) Then
' Cookie failed to decrypt
'Return
End If

' When the ticket was created, the UserData property was assigned a 
' comma delimited string of role names
Dim roles As String() = authTicket.UserData.Split(New Char() {","})

' Create an Identity object
Dim id As FormsIdentity = new FormsIdentity(authTicket)

' This principal will flow throughout the request
Dim principal As CustomPrincipal = new CustomPrincipal(id, roles)

' Attach the new principal object to the current HttpContext object
Context.User = principal

End Sub
</script>

 

 

CustomPrincipal.aspx

 

 
Imports System
Imports System.Security.Principal

Public Class CustomPrincipal 
Implements IPrincipal
Private _identity As IIdentity
Private _roles() As String
Public Sub New (ByVal identity As IIdentity, ByVal roles As String())
_identity = identity
_roles = New String(roles.Length) {}
roles.CopyTo(_roles, 0)
Array.Sort(_roles)
End Sub

' IPrincipal Implementation
Public Overridable Function IsInRole(ByVal role As String) As Boolean Implements IPrincipal.IsInRole
If Array.BinarySearch(_roles, role) >=0 Then
Return True
Else
Return False
End If
End Function

Public ReadOnly Property Identity() As IIdentity Implements IPrincipal.Identity
Get 
Return _identity
End Get
End Property

' Checks whether a principal is in all of the specified set of roles
Public Function IsInAllRoles(ByVal roles As String()) As Boolean
Dim searchrole As String
For Each searchrole In roles
If Array.BinarySearch(_roles,searchrole) < 0 Then
Return False
End If
Next
Return True
End Function

' Checks whether a principal is in any of the specified set of roles
Public Function IsInAnyRoles(ByVal roles As String()) As Boolean
Dim searchrole As String
For Each searchrole In roles
If Array.BinarySearch(_roles,searchrole) > 0 Then
Return True
End If
Next
Return False
End Function
End Class