Double Structure

' Temperature class stores the value as Double
' and delegates most of the functionality 
' to the Double implementation.
Public Class Temperature
   Implements IComparable, IFormattable

   Public Overloads Function CompareTo(ByVal obj As Object) As Integer _
       Implements IComparable.CompareTo

      If obj Is Nothing Then Return 1

      Dim temp As Temperature = TryCast(obj, Temperature)
      If temp IsNot Nothing Then
         Return m_value.CompareTo(temp.m_value)
      Else
         Throw New ArgumentException("object is not a Temperature")
      End If
   End Function

   Public Overloads Function ToString(ByVal format As String, ByVal provider As IFormatProvider) As String _
       Implements IFormattable.ToString

      If Not (format Is Nothing) Then
         If format.Equals("F") Then
            Return [String].Format("{0}'F", Me.Value.ToString())
         End If
         If format.Equals("C") Then
            Return [String].Format("{0}'C", Me.Celsius.ToString())
         End If
      End If

      Return m_value.ToString(format, provider)
   End Function

   ' Parses the temperature from a string in form
   ' [ws][sign]digits['F|'C][ws]
   Public Shared Function Parse(ByVal s As String, ByVal styles As NumberStyles, ByVal provider As IFormatProvider) As Temperature
      Dim temp As New Temperature()

      If s.TrimEnd(Nothing).EndsWith("'F") Then
         temp.Value = Double.Parse(s.Remove(s.LastIndexOf("'"c), 2), styles, provider)
      Else
         If s.TrimEnd(Nothing).EndsWith("'C") Then
            temp.Celsius = Double.Parse(s.Remove(s.LastIndexOf("'"c), 2), styles, provider)
         Else
            temp.Value = Double.Parse(s, styles, provider)
         End If
      End If
      Return temp
   End Function

   ' The value holder
   Protected m_value As Double

   Public Property Value() As Double
      Get
         Return m_value
      End Get
      Set(ByVal Value As Double)
         m_value = Value
      End Set
   End Property

   Public Property Celsius() As Double
      Get
         Return (m_value - 32) / 1.8
      End Get
      Set(ByVal Value As Double)
         m_value = Value * 1.8 + 32
      End Set
   End Property
End Class

// Temperature class stores the value as Double
// and delegates most of the functionality 
// to the Double implementation.
public class Temperature : IComparable, IFormattable
{
   // IComparable.CompareTo implementation.
   public int CompareTo(object obj)
   {
      if (obj == null) return 1;

      Temperature temp = obj as Temperature;
      if (temp != null) 
         return m_value.CompareTo(temp.m_value);
      else
         throw new ArgumentException("object is not a Temperature");
   }

   // IFormattable.ToString implementation.
   public string ToString(string format, IFormatProvider provider)
   {
      if (format != null)
      {
         if (format.Equals("F"))
         {
            return String.Format("{0}'F", this.Value.ToString());
         }
         if (format.Equals("C"))
         {
            return String.Format("{0}'C", this.Celsius.ToString());
         }
      }

      return m_value.ToString(format, provider);
   }

   // Parses the temperature from a string in form
   // [ws][sign]digits['F|'C][ws]
   public static Temperature Parse(string s, NumberStyles styles, IFormatProvider provider)
   {
      Temperature temp = new Temperature();

      if (s.TrimEnd(null).EndsWith("'F"))
      {
         temp.Value = Double.Parse(s.Remove(s.LastIndexOf('\''), 2), styles, provider);
      }
      else if (s.TrimEnd(null).EndsWith("'C"))
      {
         temp.Celsius = Double.Parse(s.Remove(s.LastIndexOf('\''), 2), styles, provider);
      }
      else
      {
         temp.Value = Double.Parse(s, styles, provider);
      }

      return temp;
   }

   // The value holder
   protected double m_value;

   public double Value
   {
      get
      {
         return m_value;
      }
      set
      {
         m_value = value;
      }
   }

   public double Celsius
   {
      get
      {
         return (m_value - 32.0) / 1.8;
      }
      set
      {
         m_value = 1.8 * value + 32.0;
      }
   }
}