/// <summary>
        /// 输出指定信息到文本文件
        /// </summary>
        /// <param name="msg">输出信息</param>
        public static void WriteMessage(string msg)
        {
            using (FileStream fs = new FileStream(@"d:\test.txt", FileMode.OpenOrCreate, FileAccess.Write))
            {
                using (StreamWriter sw = new StreamWriter(fs))
                {
                    sw.BaseStream.Seek(0, SeekOrigin.End);
                    sw.WriteLine("{0}\n", msg, DateTime.Now);
                    sw.Flush();
                }
            }
        }