程序集需要添加的引用是：ICSharpCode.SharpZipLib.dll

使用实例：

            //执行压缩
            ClsZip.Zip(downZipPath, sourceTopPath, 1, "", allFilePath);
//执行下载
            ctrlDcAllGrxx.download(downZipPath, true);

压缩文件的类ClsZip：

   public class ClsZip

    {
/// <summary>
/// 生成压缩文件
/// </summary>
/// <param name="strZipPath">生成的zip文件的路径,包括文件名</param>
/// <param name="strSourceTopDirectoryPath">要压缩的源文件的上级目录</param>
/// <param name="intZipLevel">T压缩等级</param>
/// <param name="strPassword">压缩包解压密码,不设密码""</param>
/// <param name="filesOrDirectoriesPaths">源文件路径</param>
/// <returns></returns>
        public static bool Zip(string strZipPath, string strSourceTopDirectoryPath, int intZipLevel, string strPassword, 

List<string> filesOrDirectoriesPaths)
        {
try
            {
                List<string> AllFilesPath = new List<string>();
if (filesOrDirectoriesPaths.Count > 0) // get all files path
                {
for (int i = 0; i < filesOrDirectoriesPaths.Count; i++)
                    {
if (File.Exists(filesOrDirectoriesPaths[i]))
                        {
                            AllFilesPath.Add(filesOrDirectoriesPaths[i]);
                        }
else if (Directory.Exists(filesOrDirectoriesPaths[i]))
                        {
                            GetDirectoryFiles(filesOrDirectoriesPaths[i], AllFilesPath);
                        }
                    }
                }
if (AllFilesPath.Count > 0)
                {
                    ZipOutputStream zipOutputStream = new ZipOutputStream(File.Create(strZipPath));
                    zipOutputStream.SetLevel(intZipLevel);
                    zipOutputStream.Password = strPassword;
for (int i = 0; i < AllFilesPath.Count; i++)
                    {
string strFile = AllFilesPath[i].ToString();
try
                        {
if (strFile.Substring(strFile.Length - 1) == "") //folder
                            {
string strFileName = strFile.Replace(strSourceTopDirectoryPath, "");
if (strFileName.StartsWith(""))
                                {
                                    strFileName = strFileName.Substring(1);
                                }
                                ZipEntry entry = new ZipEntry(strFileName);
                                entry.DateTime = DateTime.Now;
                                zipOutputStream.PutNextEntry(entry);
                            }
else //file
                            {
                                FileStream fs = File.OpenRead(strFile);
byte[] buffer = new byte[fs.Length];
                                fs.Read(buffer, 0, buffer.Length);
string strFileName = strFile.Replace(strSourceTopDirectoryPath, "");
if (strFileName.StartsWith(""))
                                {
                                    strFileName = strFileName.Substring(0);
                                }
                                ZipEntry entry = new ZipEntry(strFileName);
                                entry.DateTime = DateTime.Now;
                                zipOutputStream.PutNextEntry(entry);
                                zipOutputStream.Write(buffer, 0, buffer.Length);
                                fs.Close();
                                fs.Dispose();
                            }
                        }
catch
                        {
continue;
                        }
                    }
                    zipOutputStream.Finish();
                    zipOutputStream.Close();
return true;
                }
else
                {
return false;
                }
            }
catch
            {
return false;
            }
        }
/// <summary>
/// Gets the directory files.
/// </summary>
/// <param name="strParentDirectoryPath">源文件路径</param>
/// <param name="AllFilesPath">所有文件路径</param>
        public static void GetDirectoryFiles(string strParentDirectoryPath, List<string> AllFilesPath)
        {
string[] files = Directory.GetFiles(strParentDirectoryPath);
for (int i = 0; i < files.Length; i++)
            {
                AllFilesPath.Add(files[i]);
            }
string[] directorys = Directory.GetDirectories(strParentDirectoryPath);
for (int i = 0; i < directorys.Length; i++)
            {
                GetDirectoryFiles(directorys[i], AllFilesPath);
            }
if (files.Length == 0 && directorys.Length == 0) //empty folder
            {
                AllFilesPath.Add(strParentDirectoryPath);
            }
        }

    }

参考：

 ZipOutputStream类（1）

如果要完成一个文件或文件夹的压缩，则要使用ZipOutputStream类。ZipOutputStream是OutputStream的子类，常用操作方法如表所示。

 ZipOutputStream类的常用方法