On Mar 7, 8:16 am, Scott McNair
<smcn...@beachexpress.takethispartout.com> wrote:

Option Explicit On
Option Strict On
Option Infer Off

Imports System
Imports System.Runtime.InteropServices
Imports Microsoft.Win32

Public Class MainForm
   Private Shared ReadOnly HWND_BROADCAST As New IntPtr(-1)
   Private Const WM_SETTINGCHANGE As Integer = &H1A

   Private Declare Auto Function SendMessage Lib "user32" ( _
       ByVal hWnd As IntPtr, _
       ByVal Msg As Integer, _
       ByVal wParam As IntPtr, _
       ByVal lParam As String) As Integer

   Private Sub MainForm_Load(ByVal sender As Object, ByVal e As
System.EventArgs) Handles Me.Load
       LoadEnvironment()
   End Sub

   Private Sub LoadEnvironment()
       Try
           ListView1.BeginUpdate()

           ListView1.Items.Clear()

           Dim keys As New List(Of String)()
           For Each target As EnvironmentVariableTarget In
DirectCast([Enum].GetValues(GetType(EnvironmentVariableTarget)),
EnvironmentVariableTarget())
               For Each entry As DictionaryEntry In
Environment.GetEnvironmentVariables(target)
                   If Not keys.Contains(entry.Key.ToString()) Then
                       keys.Add(entry.Key.ToString())
                       Dim item As New ListViewItem(New String()
{entry.Key.ToString(), entry.Value.ToString()})
                       ListView1.Items.Add(item)
                   End If
               Next
           Next

       Catch
       Finally
           ListView1.EndUpdate()
       End Try
   End Sub

   Private Sub btnAdd_Click(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles btnAdd.Click
       Dim key As RegistryKey = OpenKey()
       key.SetValue("Baloney", "Oscar Meyer",
RegistryValueKind.String)
       key.Close()
       SendMessage(HWND_BROADCAST, WM_SETTINGCHANGE, IntPtr.Zero,
"Environment")
   End Sub

   Private Sub btnDelete_Click(ByVal sender As System.Object, ByVal e
As System.EventArgs) Handles btnDelete.Click
       Dim key As RegistryKey = OpenKey()
       key.DeleteValue("Baloney", False)
       key.Close()
       SendMessage(HWND_BROADCAST, WM_SETTINGCHANGE, IntPtr.Zero,
"Environment")
   End Sub

   Private Function OpenKey() As RegistryKey
       Return Registry.LocalMachine.OpenSubKey("System
\CurrentControlSet\Control\Session Manager\Environment", True)
   End Function

   Protected Overrides Sub WndProc(ByRef m As
System.Windows.Forms.Message)
       If m.Msg = WM_SETTINGCHANGE AndAlso
Marshal.PtrToStringAuto(m.LParam) = "Environment" Then
           LoadEnvironment()
       End If
       MyBase.WndProc(m)
   End Sub

End Class

Basically a form with a listview and a couple of buttons.  the
listview is in details view and has to columns, name and value.  It
appears that the System.Environment.GetVariables() won't refresh
unless you pass in the target type.  So, I do that, but make sure
their are no duplicates in the final list....

Kind of rough, but it seems to work ok :)  At least on XP - I suspect
you might have permission issues on Vista ;)

--
Tom Shelton