Vista - Specified cast is not valid

Hello,

I have declared a Public Class MDIMenu that Inherits from
System.Windows.Forms.Form.

In the InitializeComponent Sub I declare it as a MdiContainer with this
statement: Me.IsMdiContainer = True

In my Sub Main I start my application by calling an instance of the MDIMenu
class in this way:

Dim frm As New MDIMenu
Application.Run(frm)

I get this error: Specified cast is not valid

When I build or rebuild my solution I don't get no build error's and I can't
trace the error further than the command Application.Run(frm).

So can anyone give me a suggestion what could have gone wrong here?

I already tried to make an other, simpler form to start with, but I get the
same error.


--
RW

"RW" <RW@xxxxxx> wrote in message
news:5CBC9DF7-92CE-4E6F-B78E-FD12A193BD61@xxxxxxYou do know what *cast* means don't you? You can't cast a Windows.Control
(MDIMenu) to a System.Windows.Form. which is what Application.Run() wants is
a form.

http://msdn2.microsoft.com/en-us/lib...un(VS.71).aspx

Thanks Mr. Arnold,

yes, I know what casting is.

and I have declared the Public Class MDIMenu so that it inherits from
System.Windows.Forms.Form, so my frm is a form.

but even when I do it like this:

Dim frm As System.Windows.Forms.Form = New MDIMenu
Application.Run(frm)

still gives the same error

I even tried it with a regular form, not an inherited class, and it doesn't
work.

btw Option Strict is On


--
RW


"Mr. Arnold" wrote:

Hey thanks,

The complete code is this:


Public Sub Main()

Try
m_CurrentUser = New ApplicationUser
m_CurrentUser.NTLogin =
System.Security.Principal.WindowsIdentity.GetCurrent().Name.Substring(System.Security.Principal.WindowsIdentity.GetCurrent().Name.IndexOf("\")
+ 1).ToUpper()

Dim p As New SQLParameter("@NTLogin", m_CurrentUser.NTLogin)
Dim pl(0) As SQLParameter
pl(0) = p
Dim exm As New ExchangeManager
Dim ds As DataSet = exm.GetDataSet("SQLStatements", "GetUser", pl)

For Each dr As DataRow In ds.Tables(0).Rows

With dr
If CType(.Item("IsActive"), Boolean) Then
m_CurrentUser.PK_Gebruiker = CType(.Item("PK_User"),
Guid)
m_CurrentUser.UserFirstName =
..Item("FirstName").ToString
m_CurrentUser.UserLastname =
..Item("Lastname").ToString
m_CurrentUser.UserEmail = .Item("EMail").ToString
Else
Throw New ApplicationException("User " &
..Item("FirstName").ToString & " " & .Item("Lastname").ToString & " is
inactive!")
End If
End With
Next

If m_CurrentUser.UserEmail = System.String.Empty Then
Throw New ApplicationException(m_CurrentUser.NTLogin & " is
not a registred user!")
End If

Dim frm As New MDIMenu
Application.Run(frm)
frm.Text = "..."


Catch ex As System.Exception
If MessageBox.Show(ex.Message, "...", MessageBoxButtons.OK,
MessageBoxIcon.Exclamation) = DialogResult.OK Then
Application.Exit()
End If

End Try


End Sub

--
RW


"dlm@xxxxxx" wrote: