/// <summary>
  /// 创建一个压缩文件
  /// </summary>
  /// <param name="zipFilename">压缩后的文件名</param>
  /// <param name="sourceDirectory">待压缩文件的所在目录</param>
  public static void PackFiles(string zipFilename,string sourceDirectory)
  {
   FastZip fz = new FastZip() ;
   fz.CreateEmptyDirectories = true ;
   fz.CreateZip(zipFilename,sourceDirectory,true,"") ;
   fz = null ;
  }

  /// <summary>
  /// 解压缩文件
  /// </summary>
  /// <param name="zipFile">待解压缩的文件</param>
  /// <param name="directory">解压缩后文件存放的目录</param>
  public static bool UnpackFiles(string zipFile,string directory)
  {
   if( !Directory.Exists(directory) )
    Directory.CreateDirectory(directory) ;

   ZipInputStream zis = new ZipInputStream( File.OpenRead(zipFile) ) ;
   ZipEntry theEntry = null ;
   while( (theEntry = zis.GetNextEntry()) != null )
   {
    string directoryName = Path.GetDirectoryName(theEntry.Name) ;
    string fileName = Path.GetFileName(theEntry.Name) ;
    if( directoryName != string.Empty )
     Directory.CreateDirectory(directory + directoryName) ;

    if( fileName != string.Empty )
    {
     FileStream streamWriter = File.Create( Path.Combine( directory,theEntry.Name) ) ;
     int size = 2048 ;
     byte[] data = new byte[size] ;
     while ( true )
     {
      size = zis.Read(data,0,data.Length) ;
      if( size > 0 )
       streamWriter.Write( data,0,size ) ;
      else
       break ;
     }

     streamWriter.Close() ;
    }
   }

   zis.Close() ;
   return true ;
  }
 }
最后别忘了using ICSharpCode.SharpZipLib.Zip ;
以上代码参照 而做了小修改

另外一种方法使用Microsoft J# 类库,具体参考MSDN文章：
通过 C# 使用 J# 类库中的 Zip 类压缩文件和数据

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