文件与二进制流相互转换

        /// <summary>
        /// 把文件转换成二进制流
        /// </summary>
        /// <param name="Path">输入参数：文件位置</param>
        /// <returns></returns>
        public static byte[] ConvertFileToByte(string Path)
        {
            FileStream stream = new FileInfo(Path).OpenRead();
            byte[] buffer = new byte[stream.Length];
            stream.Read(buffer, 0, Convert.ToInt32(stream.Length));
            return buffer;
        }

        /// <summary>
        /// 讲二进制文件转换成文件
        /// </summary>
        /// <param name="data">输入参数：二进制数据流</param>
        /// <param name="Path">输入参数：将要输出文件的位置</param>
        /// <param name="FileType">输入参数：生成文件的类型（word，excel）</param>
        /// <returns>返回生成文件的位置</returns>
        public static string ConvertByteToFile(byte[] data, string Path, string FileType)
        {
            Path = Path + "." + FileType;
            FileStream fs;
            if (System.IO.File.Exists(Path))
            {
                fs = new FileStream(Path, FileMode.Truncate);
            }
            else
            {
                fs = new FileStream(Path, FileMode.CreateNew);
            }
            BinaryWriter br = new BinaryWriter(fs);
            br.Write(data, 0, data.Length);
            br.Close();
            fs.Close();
            return Path;
        }