1.利用.net自带的压缩和解压缩方法GZip

参考代码如下：

//========================================================================      //  类名: CommonCompress     /// <summary>     /// 用于对文件和字符串进行压缩      /// </summary>     /// <remarks>     /// 用于对文件和字符串进行压缩      /// </remarks>     /*=======================================================================      变更记录      序号　　　更新日期　　开发者　　　变更内容      0001　　　2008/07/22  张          新建      =======================================================================*/     public class CommonCompress      {          /// <summary>         /// 压缩字符串          /// </summary>         /// <param name="strUncompressed">未压缩的字符串</param>         /// <returns>压缩的字符串</returns>         public static string StringCompress(string strUncompressed)          {              byte[] bytData = System.Text.Encoding.Unicode.GetBytes(strUncompressed);              MemoryStream ms = new MemoryStream();              Stream s = new GZipStream(ms, CompressionMode.Compress);              s.Write(bytData, 0, bytData.Length);              s.Close();              byte[] dataCompressed = (byte[])ms.ToArray();              return System.Convert.ToBase64String(dataCompressed, 0, dataCompressed.Length);          }            /// <summary>         /// 解压缩字符串          /// </summary>         /// <param name="strCompressed">压缩的字符串</param>         /// <returns>未压缩的字符串</returns>         public static string StringDeCompress(string strCompressed)          {              System.Text.StringBuilder strUncompressed = new System.Text.StringBuilder();              int totalLength = 0;              byte[] bInput = System.Convert.FromBase64String(strCompressed); ;              byte[] dataWrite = new byte[4096];              Stream s = new GZipStream(new MemoryStream(bInput), CompressionMode.Decompress);              while (true)              {                  int size = s.Read(dataWrite, 0, dataWrite.Length);                  if (size > 0)                  {                      totalLength += size;                      strUncompressed.Append(System.Text.Encoding.Unicode.GetString(dataWrite, 0, size));                  }                  else                 {                      break;                  }              }              s.Close();              return strUncompressed.ToString();          }            /// <summary>         /// 压缩文件          /// </summary>         /// <param name="iFile">压缩前文件路径</param>         /// <param name="oFile">压缩后文件路径</param>         public static void CompressFile(string iFile, string oFile)          {              //判断文件是否存在             if (File.Exists(iFile) == false)              {                  throw new FileNotFoundException("文件未找到!");              }              //创建文件流             byte[] buffer = null;              FileStream iStream = null;              FileStream oStream = null;              GZipStream cStream = null;              try             {                  //把文件写进数组                 iStream = new FileStream(iFile, FileMode.Open, FileAccess.Read, FileShare.Read);                  buffer = new byte[iStream.Length];                  int num = iStream.Read(buffer, 0, buffer.Length);                  if (num != buffer.Length)                  {                      throw new ApplicationException("压缩文件异常!");                  }                  //创建文件输出流并输出                 oStream = new FileStream(oFile, FileMode.OpenOrCreate, FileAccess.Write);                  cStream = new GZipStream(oStream, CompressionMode.Compress, true);                  cStream.Write(buffer, 0, buffer.Length);              }              finally             {                  //关闭流对象                 if (iStream != null) iStream.Close();                  if (cStream != null) cStream.Close();                  if (oStream != null) oStream.Close();              }          }            /// <summary>         /// 解压缩文件          /// </summary>         /// <param name="iFile">压缩前文件路径</param>         /// <param name="oFile">压缩后文件路径</param>         public static void DecompressFile(string iFile, string oFile)          {              //判断文件是否存在             if (File.Exists(iFile) == false)              {                  throw new FileNotFoundException("文件未找到!");              }              //创建文件流             FileStream iStream = null;              FileStream oStream = null;              GZipStream dStream = null;              byte[] qBuffer = new byte[4];              try             {                  //把压缩文件写入数组                 iStream = new FileStream(iFile, FileMode.Open);                  dStream = new GZipStream(iStream, CompressionMode.Decompress, true);                  int position = (int)iStream.Length - 4;                  iStream.Position = position;                  iStream.Read(qBuffer, 0, 4);                  iStream.Position = 0;                  int num = BitConverter.ToInt32(qBuffer, 0);                  byte[] buffer = new byte[num + 100];                  int offset = 0, total = 0;                  while (true)                  {                      int bytesRead = dStream.Read(buffer, offset, 100);                      if (bytesRead == 0) break;                      offset += bytesRead;                      total += bytesRead;                  }                  //创建输出流并输出                 oStream = new FileStream(oFile, FileMode.Create);                  oStream.Write(buffer, 0, total);                  oStream.Flush();              }              finally             {                  //关闭流对象                 if (iStream != null) iStream.Close();                  if (dStream != null) dStream.Close();                  if (oStream != null) oStream.Close();              }          }      }

2.利用ICSharpCode的压缩和解压缩方法,需引用ICSharpCode.SharpZipLib.dll,这个类库是开源的，源码地址http://www.icsharpcode.net/OpenSource/SharpZipLib/Download.aspx

参考代码如下：

using System;using System.Collections.Generic; using System.IO;using ICSharpCode.SharpZipLib.Zip;using ICSharpCode.SharpZipLib.Checksums;namespace ZYBNET.FW.Utility.CommonMethod  {      //========================================================================      //  类名: ZipHelper     /// <summary>     /// 用于对文件和字符串进行压缩      /// </summary>     /// <remarks>     /// 用于对文件和字符串进行压缩      /// </remarks>     /*=======================================================================      变更记录      序号　　　更新日期　　开发者　　　变更内容      0001　　　2008/07/22  张          新建      =======================================================================*/     public class ZipHelper      {          #region 压缩文件夹,支持递归          /// <summary>         ///　压缩文件夹          /// </summary>         /// <param name="dir">待压缩的文件夹</param>         /// <param name="targetFileName">压缩后文件路径（包括文件名）</param>         /// <param name="recursive">是否递归压缩</param>         /// <returns></returns>         public static bool Compress(string dir, string targetFileName, bool recursive)          {              //如果已经存在目标文件，询问用户是否覆盖             if (File.Exists(targetFileName))              {                  throw new Exception("同名文件已经存在！");              }              string[] ars = new string[2];              if (recursive == false)              {                  ars[0] = dir;                  ars[1] = targetFileName;                  return ZipFileDictory(ars);              }                FileStream zipFile;              ZipOutputStream zipStream;                //打开压缩文件流             zipFile = File.Create(targetFileName);              zipStream = new ZipOutputStream(zipFile);                if (dir != String.Empty)              {                  CompressFolder(dir, zipStream, dir);              }                //关闭压缩文件流             zipStream.Finish();              zipStream.Close();                if (File.Exists(targetFileName))                  return true;              else                 return false;          }            /// <summary>         /// 压缩目录          /// </summary>         /// <param name="args">数组(数组[0]: 要压缩的目录; 数组[1]: 压缩的文件名)</param>         public static bool ZipFileDictory(string[] args)          {              ZipOutputStream zStream = null;              try             {                  string[] filenames = Directory.GetFiles(args[0]);                  Crc32 crc = new Crc32();                  zStream = new ZipOutputStream(File.Create(args[1]));                  zStream.SetLevel(6);                  //循环压缩文件夹中的文件                 foreach (string file in filenames)                  {                      //打开压缩文件                     FileStream fs = File.OpenRead(file);                      byte[] buffer = new byte[fs.Length];                      fs.Read(buffer, 0, buffer.Length);                      ZipEntry entry = new ZipEntry(file);                      entry.DateTime = DateTime.Now;                      entry.Size = fs.Length;                      fs.Close();                      crc.Reset();                      crc.Update(buffer);                      entry.Crc = crc.Value;                      zStream.PutNextEntry(entry);                      zStream.Write(buffer, 0, buffer.Length);                  }              }              catch             {                  throw;              }              finally             {                  zStream.Finish();                  zStream.Close();              }              return true;          }            /// <summary>         /// 压缩某个子文件夹          /// </summary>         /// <param name="basePath">待压缩路径</param>         /// <param name="zips">压缩文件流</param>         /// <param name="zipfolername">待压缩根路径</param>               private static void CompressFolder(string basePath, ZipOutputStream zips, string zipfolername)          {              if (File.Exists(basePath))              {                  AddFile(basePath, zips, zipfolername);                  return;              }              string[] names = Directory.GetFiles(basePath);              foreach (string fileName in names)              {                  AddFile(fileName, zips, zipfolername);              }                names = Directory.GetDirectories(basePath);              foreach (string folderName in names)              {                  CompressFolder(folderName, zips, zipfolername);              }            }            /// <summary>         ///　压缩某个子文件          /// </summary>         /// <param name="fileName">待压缩文件</param>         /// <param name="zips">压缩流</param>         /// <param name="zipfolername">待压缩根路径</param>         private static void AddFile(string fileName, ZipOutputStream zips, string zipfolername)          {              if (File.Exists(fileName))              {                  CreateZipFile(fileName, zips, zipfolername);              }          }            /// <summary>         /// 压缩单独文件          /// </summary>         /// <param name="FileToZip">待压缩文件</param>         /// <param name="zips">压缩流</param>         /// <param name="zipfolername">待压缩根路径</param>         private static void CreateZipFile(string FileToZip, ZipOutputStream zips, string zipfolername)          {              try             {                  FileStream StreamToZip = new FileStream(FileToZip, FileMode.Open, FileAccess.Read);                  string temp = FileToZip;                  string temp1 = zipfolername;                  if (temp1.Length > 0)                  {                      temp = temp.Replace(zipfolername + "\\", "");                  }                  ZipEntry ZipEn = new ZipEntry(temp);                    zips.PutNextEntry(ZipEn);                  byte[] buffer = new byte[16384];                  System.Int32 size = StreamToZip.Read(buffer, 0, buffer.Length);                  zips.Write(buffer, 0, size);                  try                 {                      while (size < StreamToZip.Length)                      {                          int sizeRead = StreamToZip.Read(buffer, 0, buffer.Length);                          zips.Write(buffer, 0, sizeRead);                          size += sizeRead;                      }                  }                  catch (System.Exception ex)                  {                      throw ex;                  }                    StreamToZip.Close();              }              catch             {                  throw;              }          }          #endregion         #region 解压缩          /// <summary>             /// 功能：解压zip格式的文件。             /// </summary>             /// <param name="zipFilePath">压缩文件路径</param>             /// <param name="unZipDir">解压文件存放路径,为空时默认与压缩文件同一级目录下，跟压缩文件同名的文件夹</param>             /// <returns>解压是否成功</returns>             public static void UnZipFile(string zipFilePath, string unZipDir)          {                 if (zipFilePath == string.Empty)              {                  throw new Exception("压缩文件不能为空！");              }              if (!File.Exists(zipFilePath))              {                  throw new Exception("压缩文件不存在！");              }              //解压文件夹为空时默认与压缩文件同一级目录下，跟压缩文件同名的文件夹                if (unZipDir == string.Empty)                  unZipDir = zipFilePath.Replace(Path.GetFileName(zipFilePath), Path.GetFileNameWithoutExtension(zipFilePath));              if (!unZipDir.EndsWith("//"))                  unZipDir += "//";              if (!Directory.Exists(unZipDir))                  Directory.CreateDirectory(unZipDir);                try             {                  using (ZipInputStream s = new ZipInputStream(File.OpenRead(zipFilePath)))                  {                      ZipEntry theEntry;                      while ((theEntry = s.GetNextEntry()) != null)                      {                          string directoryName = Path.GetDirectoryName(theEntry.Name);                          string fileName = Path.GetFileName(theEntry.Name);                          if (directoryName.Length > 0)                          {                              Directory.CreateDirectory(unZipDir + directoryName);                          }                          if (!directoryName.EndsWith("//"))                              directoryName += "//";                          if (fileName != String.Empty)                          {                              using (FileStream streamWriter = File.Create(unZipDir + theEntry.Name))                              {                                  int size = 2048;                                  byte[] data = new byte[2048];                                  while (true)                                  {                                      size = s.Read(data, 0, data.Length);                                      if (size > 0)                                      {                                          streamWriter.Write(data, 0, size);                                      }                                      else                                     {                                          break;                                      }                                  }                              }                          }                      }                  }              }              catch               {                  throw;              }          }          #endregion     }  }

3.利用java的压缩和解压缩方法,需引用vjslib.dll

至于这种方法的使用，大家可以去查阅msdn,这里就不写了

4.利用zlibwapi.dll的API进行压缩

据说压缩效率比较好，但是在网上没找到供下载的链接，有兴趣的朋友可以试试

5.使用System.IO.Packaging压缩和解压

System.IO.Packaging在WindowsBase.dll程序集下，使用时需要添加对WindowsBase的引用

/// <summary>         /// Add a folder along with its subfolders to a Package          /// </summary>         /// <param name="folderName">The folder to add</param>         /// <param name="compressedFileName">The package to create</param>         /// <param name="overrideExisting">Override exsisitng files</param>         /// <returns></returns>         static bool PackageFolder(string folderName, string compressedFileName, bool overrideExisting)          {              if (folderName.EndsWith(@"\"))                  folderName = folderName.Remove(folderName.Length - 1);              bool result = false;              if (!Directory.Exists(folderName))              {                  return result;              }                if (!overrideExisting && File.Exists(compressedFileName))              {                  return result;              }              try             {                  using (Package package = Package.Open(compressedFileName, FileMode.Create))                  {                      var fileList = Directory.EnumerateFiles(folderName, "*", SearchOption.AllDirectories);                      foreach (string fileName in fileList)                      {                                                   //The path in the package is all of the subfolders after folderName                         string pathInPackage;                          pathInPackage = Path.GetDirectoryName(fileName).Replace(folderName, string.Empty) + "/" + Path.GetFileName(fileName);                            Uri partUriDocument = PackUriHelper.CreatePartUri(new Uri(pathInPackage, UriKind.Relative));                          PackagePart packagePartDocument = package.CreatePart(partUriDocument,"", CompressionOption.Maximum);                          using (FileStream fileStream = new FileStream(fileName, FileMode.Open, FileAccess.Read))                          {                              fileStream.CopyTo(packagePartDocument.GetStream());                          }                      }                  }                  result = true;              }              catch (Exception e)              {                  throw new Exception("Error zipping folder " + folderName, e);              }                           return result;          }       /// <summary>         /// Compress a file into a ZIP archive as the container store          /// </summary>         /// <param name="fileName">The file to compress</param>         /// <param name="compressedFileName">The archive file</param>         /// <param name="overrideExisting">override existing file</param>         /// <returns></returns>         static bool PackageFile(string fileName, string compressedFileName, bool overrideExisting)          {              bool result = false;                if (!File.Exists(fileName))              {                  return result;              }                if (!overrideExisting && File.Exists(compressedFileName))              {                  return result;              }                try             {                  Uri partUriDocument = PackUriHelper.CreatePartUri(new Uri(Path.GetFileName(fileName), UriKind.Relative));                                   using (Package package = Package.Open(compressedFileName, FileMode.OpenOrCreate))                  {                      if (package.PartExists(partUriDocument))                      {                          package.DeletePart(partUriDocument);                      }                         PackagePart packagePartDocument = package.CreatePart(partUriDocument, "", CompressionOption.Maximum);                      using (FileStream fileStream = new FileStream(fileName, FileMode.Open, FileAccess.Read))                      {                          fileStream.CopyTo(packagePartDocument.GetStream());                      }                  }                  result = true;              }              catch (Exception e)              {                  throw new Exception("Error zipping file " + fileName, e);              }                            return result;          }      }       3、zip文件解压    Code/// <summary>         /// Extract a container Zip. NOTE: container must be created as Open Packaging Conventions (OPC) specification          /// </summary>         /// <param name="folderName">The folder to extract the package to</param>         /// <param name="compressedFileName">The package file</param>         /// <param name="overrideExisting">override existing files</param>         /// <returns></returns>         static bool UncompressFile(string folderName, string compressedFileName, bool overrideExisting)          {              bool result = false;              try             {                  if (!File.Exists(compressedFileName))                  {                      return result;                  }                    DirectoryInfo directoryInfo = new DirectoryInfo(folderName);                  if (!directoryInfo.Exists)                      directoryInfo.Create();