从指定颜色组中随机取色

        public Color RetrieveRandomColorFromList(int index)
        {
            Color[] colors = new Color[] { Color.Black, Color.Red, Color.Blue,
                Color.DarkOrange, Color.DarkRed, Color.DarkGreen, Color.DarkViolet};
            //Color[] colors = RetrieveKnownColorList();
            int count = colors.Length;
            int[] array = new int[count];
            for (int i = 0; i < array.Length; i++)
            {
                array[i] = i;
            }

            Permute<int>(array);

            return colors[array[index]];
        }

        static void Permute<T>(T[] array)
        {
            Random random = new Random();
            for (int i = 1; i < array.Length; i++)
            {
                Swap<T>(array, i, random.Next(0, i));
            }
        }

        static void Swap<T>(T[] array, int indexA, int indexB)
        {
            T temp = array[indexA];
            array[indexA] = array[indexB];
            array[indexB] = temp;
        }

        private Color[] RetrieveKnownColorList()
        {
            string[] colorArray = Enum.GetNames(typeof(System.Drawing.KnownColor));
            Color[] knownColorArray = new Color[colorArray.Length];
            int i=0;
            foreach (string colorName in colorArray)
            {
                knownColorArray[i] = Color.FromName(colorName);
                i++;
            }
           
            return knownColorArray;
        }

 

使用时，直接 RetrieveRandomColorFromList(索引号) 即可。