Imports System.Reflection
 
Public Class GUIAccess
 
    Public Delegate Sub SetTextDelegate(ByVal uC As Object, ByVal t As String)
 
    Public Shared Sub SetControlText(ByVal userControl As Control, ByVal Text _
      As String)
        If (userControl Is Nothing) Then
            Throw New ArgumentNullException("Kein Steuerelement angegeben.")
        End If
        Try
            If userControl.InvokeRequired() Then
                userControl.Invoke(New SetTextDelegate(AddressOf _
                  SetControlText), userControl, Text)
            Else
                userControl.Text = Text
            End If
        Catch ex As Exception
            MsgBox(ex.ToString)
        End Try
    End Sub
 
End Class

Label1.Text = "1234"

GUIAccess.SetControlText(Label1,"1234")