C# Hex Colour to RGB

I have to do a lot of interop work with Word & Excel and generally struggle matching up colour pallets across the two applications and the only way I've found to consistently do this is by using RGB colours and the RGB function provided in VB(A).

Having recently started a new C# project that I am using hex colour codes with (e.g. #000000), I thought I would write a simple RGB colour handling class that converts the hex colour code into RGB codes for me. And here it is...

/// A helper class used to hold the RGB values of a hex colour e.g. #000000
/// </summary>
public class RGBColour
{
 private string _HexRef = String.Empty;
 public string HexRef
 {
  get { return this._HexRef; }
  set
  {
   if (!value.StartsWith("#"))
    throw new Exception("The hex colour reference must start with a #. e.g. #000000");
   if (value.Length < 7)
    throw new Exception("The hex colour reference must be 7 characters. e.g. #000000");
   this._HexRef = value;
   Color c = ColorTranslator.FromHtml(value);
   this._R = Convert.ToInt32(c.R);
   this._G = Convert.ToInt32(c.G);
   this._B = Convert.ToInt32(c.B);
  }
 }

 private int _R = 0;
 public int R { get { return this._R; } }

 private int _G = 0;
 public int G { get { return this._G; } }

 private int _B = 0;
 public int B { get { return this._B; } }

 public RGBColour()
 {
 }
 public RGBColour(string hexRef)
 {
  this.HexRef = hexRef;
 }
} 

It quite simply uses the System.Drawing.ColorTranslator.FromHtml method to convert the hex value into a System.Drawing.Color object. The Color RGB properties are then converted to an int32.

This can then be used like this...

RGBColour rgb = new RGBColour("#000000");
xl.ActiveCell.Interior.Color = xl.RGB(rgb.R, rgb.G, rgb.B);