HowTo: List all known color names and find name of given color at WPF

This is my answer at
http://stackoverflow.com/questions/4475391/wpf-silverlight-find-the-name-of-a-color

Modified answer from Thomas Levesque to populate the Dictionary only when 1st needed, instead of taking the cost at startup (going to use at speech recognition-driven turtle graphics, so that user can pronounce known color names to change the turtle’s pen color)

1. //Project: SpeechTurtle (http://SpeechTurtle.codeplex.com)
2. //Filename: ColorUtils.cs
3. //Version: 20150901
4.  
5. using System.Collections.Generic;
6. using System.Linq;
7. using System.Reflection;
8. using System.Windows.Media;
9.  
10. namespace SpeechTurtle.Utils
11. {
12.   /// <summary>
13.   /// Color-related utility methods
14.   /// </summary>
15.   public static class ColorUtils //based on http://stackoverflow.com/questions/4475391/wpf-silverlight-find-the-name-of-a-color
16.   {
17.     #region — Fields —
18.  
19.     private static Dictionary<string, Color> knownColors; //=null
20.  
21.     #endregion
22.  
23.     #region — Methods —
24.  
25.     #region Extension methods
26.  
27.     public static string GetKnownColorName(this Color color)
28.     {
29.       return GetKnownColors()
30.           .Where(kvp => kvp.Value.Equals(color))
31.           .Select(kvp => kvp.Key)
32.           .FirstOrDefault();
33.     }
34.  
35.     public static Color GetKnownColor(this string name)
36.     {
37.       Color color;
38.       return GetKnownColors().TryGetValue(name, out color) ? color : Colors.Black; //if color for name is not found, return black
39.     }
40.  
41.     #endregion
42.  
43.     public static Dictionary<string, Color> GetKnownColors()
44.     {
45.       if (knownColors == null)
46.       {
47.         var colorProperties = typeof(Colors).GetProperties(BindingFlags.Static | BindingFlags.Public);
48.         knownColors = colorProperties.ToDictionary(
49.           p => p.Name,
50.           p => (Color)p.GetValue(null, null));
51.       }
52.       return knownColors;
53.     }
54.  
55.     public static string[] GetKnownColorNames()
56.     {
57.       return GetKnownColors().Keys.ToArray();
58.     }
59.  
60.     #endregion
61.   }
62. }