Encrypting a dataset using AES, including compression

''' <summary>
''' This class calculates a linear gradient brush to represent the password strength
''' </summary>
Public Class ForegroundConverter
   Implements System.Windows.Data.IValueConverter
   ''' <summary>
   ''' Converts a value. 
   ''' </summary>
   ''' <param name="value">The password strength (0 to 100)</param>
   ''' <param name="targetType">The type of the binding target property.</param>
   ''' <param name="parameter">The converter parameter to use.</param>
   ''' <param name="culture">The culture to use in the converter.</param>
   ''' <returns>A brush that paints an area with a linear gradient. </returns>
   Public Function Convert(value As Object, targetType As System.Type, parameter As Object, culture As System.Globalization.CultureInfo) _
      As Object _
      Implements System.Windows.Data.IValueConverter.Convert

      Dim strength As Double = value
      Dim brush As System.Windows.Media.LinearGradientBrush = New System.Windows.Media.LinearGradientBrush()

      brush.StartPoint = New System.Windows.Point(0, 0.5)
      brush.EndPoint = New System.Windows.Point(1, 0.5)

      If (strength <= 33) Then
         brush.GradientStops.Add(New System.Windows.Media.GradientStop(System.Windows.Media.Colors.Red, 0))
      ElseIf (strength <= 66) Then
         brush.GradientStops.Add(New System.Windows.Media.GradientStop(System.Windows.Media.Colors.Red, 0))
         brush.GradientStops.Add(New System.Windows.Media.GradientStop(System.Windows.Media.Colors.Yellow, (1 / strength) * 33))
      Else
         brush.GradientStops.Add(New System.Windows.Media.GradientStop(System.Windows.Media.Colors.Red, 0))
         brush.GradientStops.Add(New System.Windows.Media.GradientStop(System.Windows.Media.Colors.Yellow, (1 / strength) * 33))
         brush.GradientStops.Add(New System.Windows.Media.GradientStop(System.Windows.Media.Colors.Green, ((1 / strength) * 33) * 2))
      End If

      Return brush
   End Function

   ''' <summary>
   ''' Converts a value. 
   ''' </summary>
   ''' <param name="value">The value that is produced by the binding target.</param>
   ''' <param name="targetType">The type to convert to.</param>
   ''' <param name="parameter">The converter parameter to use.</param>
   ''' <param name="culture">The culture to use in the converter.</param>
   ''' <returns>Never returns a value</returns>
   ''' <exception cref="System.NotImplementedException">Thrown always</exception>
   Public Function ConvertBack(value As Object, targetType As Type, parameter As Object, culture As System.Globalization.CultureInfo) _
      As Object _
      Implements System.Windows.Data.IValueConverter.ConvertBack

      Throw New System.NotImplementedException()
   End Function
End Class