Visual Basic

'example - store a string holding a folder location<br />
Dim backupFolder As String<br />
'ubstantiate a RegistryKey object<br />
Dim regEntry As Microsoft.Win32.RegistryKey<br />
'set it to the location we want:<br />
regEntry = Microsoft.Win32.Registry.CurrentUser.OpenSubKey("SOFTWARE\\TestApp", True)<br />
'if this is first run then it wont exist yet so create it:<br />
If regEntry Is Nothing Then<br />
    regEntry = Microsoft.Win32.Registry.CurrentUser.CreateSubKey("SOFTWARE\\TestApp")<br />
    'create a subkey:<br />
    regEntry.SetValue("Backup Path", Environment.GetFolderPath(Environment.SpecialFolder.Personal) & "\Backup")<br />
End If<br />
'check we have a usable value in the subkey (and that the subkey exists)<br />
If regEntry.GetValue("Backup Path").ToString = "" Or regEntry.GetValue("Backup Path").ToString = Nothing Then<br />
    'set it to default path<br />
    regEntry.SetValue("Backup Path", Environment.GetFolderPath(Environment.SpecialFolder.Personal) & "\Backup")<br />
End If<br />
'set backupfolder <br />
backupFolder = regEntry.GetValue("Backup Path").ToString<br />
Me.Text = "Current backup folder: " & backupFolder

Private Sub TextBox1_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles TextBox1.KeyDown<br />
    If (e.KeyCode = Keys.Up OrElse e.KeyCode = Keys.Down) AndAlso IsNumeric(Me.TextBox1.Text) Then<br />
        Dim i As Integer = CInt(Me.TextBox1.Text)<br />
        'check key again, if it is up add 1, otherwise add -1<br />
        i += IIf(e.KeyCode = Keys.Up, 1, -1)<br />
        Me.TextBox1.Text = i.ToString<br />
        'start text selection at end of text, length 0 to move caret<br />
        Me.TextBox1.SelectionStart = Me.TextBox1.Text.Length<br />
        Me.TextBox1.SelectionLength = 0<br />
        e.Handled = True<br />
    End If<br />
    <br />
End Sub