C#ICSharpCodeを使用する.SharpZipLibファイルの圧縮

 public static bool ZipTxtFile(string FileToZip, string ZipedFile, string ZipedFileName, int BlockSize)
        {
            try
            {
                FileStream StreamToZip = new FileStream(FileToZip, FileMode.Open, FileAccess.Read);
                if (File.Exists(ZipedFile))
                {
                    File.Delete(ZipedFile);
                }
                FileStream ZipFile = File.Create(ZipedFile);
                ZipOutputStream ZipStream = new ZipOutputStream(ZipFile);
                ZipEntry ZipEntry = new ZipEntry(ZipedFileName);
                ZipStream.PutNextEntry(ZipEntry);

                ZipStream.SetLevel(6);
                byte[] buffer = new byte[BlockSize];
                Int32 size = StreamToZip.Read(buffer, 0, buffer.Length);
                ZipStream.Write(buffer, 0, size);
                try
                {
                    while (size < StreamToZip.Length)
                    {
                        int sizeRead = StreamToZip.Read(buffer, 0, buffer.Length);
                        ZipStream.Write(buffer, 0, sizeRead);
                        size += sizeRead;
                    }
                }
                catch (Exception err)
                {
                    SystemLog.logger(err.InnerException.Message);
                    return false;
                }
                ZipStream.Finish();
                ZipStream.Close();
                StreamToZip.Close();
                return true;
            }
            catch (Exception ex)
            {
                SystemLog.logger(ex.InnerException.Message);
                return false;
            }
        }

public static bool ZipFile(string filename)
        {
            bool isSuccess = false;
            string zipPath = "C:";
            try
            {
                zipPath = System.Configuration.ConfigurationManager.AppSettings["ZipPath"];
                FileStream fsTemp = File.OpenRead(filename);
                string fileNameWithoutExtension = Path.GetFileNameWithoutExtension(filename);
                string fileNameWithExtension = Path.GetFileName(filename);
                if (!zipPath.EndsWith(Path.DirectorySeparatorChar.ToString()))
                {
                    zipPath = zipPath + Path.DirectorySeparatorChar.ToString();
                }
                isSuccess = FileUtility.ZipTxtFile(filename, zipPath + "request_" + fileNameWithoutExtension + ".zip", fileNameWithExtension, Convert.ToInt32(fsTemp.Length));
                fsTemp.Close();

                return isSuccess;
            }
            catch (Exception e)
            {
                isSuccess = false;
                SystemLog.logger(e.InnerException.Message);
                return isSuccess;
            }
        }

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