int count_high = 0, count_lower = 0;
            if (count_high == 0 && Label1.Text == max)
            {
                Label1.ForeColor = System.Drawing.Color.Red;
                count_high++;
            }
            if (count_lower == 0 && Label1.Text == min)
            {
                Label1.ForeColor = System.Drawing.Color.Red;
                count_lower++;
            }

------解决方案--------------------

C# code

 //将八个分数放到一个数组，我下面的以int型数组为例（当然你的是float数组）
         int[] arr = {9,12,1, 2, 4, 5, 6 };
            ArrayList list = new ArrayList(arr);
            list.Sort();
            int min = Convert.ToInt32(list[0]);
            int max = Convert.ToInt32(list[list.Count - 1]);
            Response.Write("最大" + max + " 最小:" + min); //输出12,1