C# 生成随机阿拉伯数字，或字符串

//TextBox1.Text = TongYong.SuiJi.SuiJiMingZi(2);    
public class SuiJi
    {
        //TextBox1.Text = TongYong.SuiJi.SuiJiMingZi(2);
        #region 生成随机阿拉伯数字
        /// <summary>
        /// 产生随机数
        /// </summary>
        private static char[] constant =   
      {   
        '0','1','2','3','4','5','6','7','8','9',   
      };
        public static string SuiJiNumber(int Length)
        {
            System.Text.StringBuilder newRandom = new System.Text.StringBuilder(10);
            Random rd = new Random();
            for (int i = 0; i < Length; i++)
            {
                newRandom.Append(constant[rd.Next(10)]);
            }
            return newRandom.ToString();
        }
        #endregion
    }