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[ASP.net教程]C# 压缩文件


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   上一节讲述了C# WebApi传参之Post请求-AJAX

   本节探讨C#压缩文件的方法,直接上代码

   如下

 public class ZipUtility  {    /// <summary>     /// 所有文件缓存     /// </summary>     List<string> files = new List<string>();    /// <summary>     /// 所有空目录缓存     /// </summary>     List<string> paths = new List<string>();    /// <summary>     /// 压缩单个文件     /// </summary>     /// <param name="fileToZip">要压缩的文件</param>     /// <param name="zipedFile">压缩后的文件全名</param>     /// <param name="compressionLevel">压缩程度,范围0-9,数值越大,压缩程序越高</param>     /// <param name="blockSize">分块大小</param>     public void ZipFile(string fileToZip, string zipedFile, int compressionLevel, int blockSize)    {      if (!System.IO.File.Exists(fileToZip))//如果文件没有找到,则报错       {        throw new FileNotFoundException("The specified file " + fileToZip + " could not be found. Zipping aborderd");      }      FileStream streamToZip = new FileStream(fileToZip, FileMode.Open, FileAccess.Read);      FileStream zipFile = File.Create(zipedFile);      ZipOutputStream zipStream = new ZipOutputStream(zipFile);      ZipEntry zipEntry = new ZipEntry(fileToZip);      zipStream.PutNextEntry(zipEntry);      zipStream.SetLevel(compressionLevel);      byte[] buffer = new byte[blockSize];      int 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 ex)      {        GC.Collect();        throw ex;      }      zipStream.Finish();      zipStream.Close();      streamToZip.Close();      GC.Collect();    }    /// <summary>     /// 压缩目录(包括子目录及所有文件)     /// </summary>     /// <param name="rootPath">要压缩的根目录</param>     /// <param name="destinationPath">保存路径</param>     /// <param name="compressLevel">压缩程度,范围0-9,数值越大,压缩程序越高</param>     public void ZipFileFromDirectory(string rootPath, string destinationPath, int compressLevel)    {      GetAllDirectories(rootPath);      /* while (rootPath.LastIndexOf("\\") + 1 == rootPath.Length)//检查路径是否以"\"结尾       {       rootPath = rootPath.Substring(0, rootPath.Length - 1);//如果是则去掉末尾的"\"       }       */      //string rootMark = rootPath.Substring(0, rootPath.LastIndexOf("\\") + 1);//得到当前路径的位置,以备压缩时将所压缩内容转变成相对路径。       string rootMark = rootPath + "\\";//得到当前路径的位置,以备压缩时将所压缩内容转变成相对路径。       Crc32 crc = new Crc32();      ZipOutputStream outPutStream = new ZipOutputStream(File.Create(destinationPath));      outPutStream.SetLevel(compressLevel); // 0 - store only to 9 - means best compression       foreach (string file in files)      {        FileStream fileStream = File.OpenRead(file);//打开压缩文件         byte[] buffer = new byte[fileStream.Length];        fileStream.Read(buffer, 0, buffer.Length);        ZipEntry entry = new ZipEntry(file.Replace(rootMark, string.Empty));        entry.DateTime = DateTime.Now;         entry.Size = fileStream.Length;        fileStream.Close();        crc.Reset();        crc.Update(buffer);        entry.Crc = crc.Value;        outPutStream.PutNextEntry(entry);        outPutStream.Write(buffer, 0, buffer.Length);      }      this.files.Clear();      foreach (string emptyPath in paths)      {        ZipEntry entry = new ZipEntry(emptyPath.Replace(rootMark, string.Empty) + "/");        outPutStream.PutNextEntry(entry);      }      this.paths.Clear();      outPutStream.Finish();      outPutStream.Close();      GC.Collect();    }    /// <summary>     /// 取得目录下所有文件及文件夹,分别存入files及paths     /// </summary>     /// <param name="rootPath">根目录</param>     private void GetAllDirectories(string rootPath)    {      string[] subPaths = Directory.GetDirectories(rootPath);//得到所有子目录       foreach (string path in subPaths)      {        GetAllDirectories(path);//对每一个字目录做与根目录相同的操作:即找到子目录并将当前目录的文件名存入List       }      string[] files = Directory.GetFiles(rootPath);      foreach (string file in files)      {        this.files.Add(file);//将当前目录中的所有文件全名存入文件List       }      if (subPaths.Length == files.Length && files.Length == 0)//如果是空目录       {        this.paths.Add(rootPath);//记录空目录       }    }    /// <summary>     /// 解压缩文件(压缩文件中含有子目录)     /// </summary>     /// <param name="zipfilepath">待解压缩的文件路径</param>     /// <param name="unzippath">解压缩到指定目录</param>     /// <returns>解压后的文件列表</returns>     public List<string> UnZip(string zipfilepath, string unzippath)    {      //解压出来的文件列表       List<string> unzipFiles = new List<string>();      //检查输出目录是否以“\\”结尾       if (unzippath.EndsWith("\\") == false || unzippath.EndsWith(":\\") == false)      {        unzippath += "\\";      }      ZipInputStream s = new ZipInputStream(File.OpenRead(zipfilepath));      ZipEntry theEntry;      while ((theEntry = s.GetNextEntry()) != null)      {        string directoryName = Path.GetDirectoryName(unzippath);        string fileName = Path.GetFileName(theEntry.Name);        //生成解压目录【用户解压到硬盘根目录时,不需要创建】         if (!string.IsNullOrEmpty(directoryName))        {          Directory.CreateDirectory(directoryName);        }        if (fileName != String.Empty)        {          //如果文件的压缩后大小为0那么说明这个文件是空的,因此不需要进行读出写入           if (theEntry.CompressedSize == 0)            continue;          //解压文件到指定的目录           directoryName = Path.GetDirectoryName(unzippath + theEntry.Name);          //建立下面的目录和子目录           Directory.CreateDirectory(directoryName);          //记录导出的文件           unzipFiles.Add(unzippath + theEntry.Name);          FileStream streamWriter = File.Create(unzippath + 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;            }          }          streamWriter.Close();        }      }      s.Close();      GC.Collect();      return unzipFiles;    }    public string GetZipFileExtention(string fileFullName)    {      int index = fileFullName.LastIndexOf(".");      if (index <= 0)      {        throw new Exception("The source package file is not a compress file");      }      //extension string      string ext = fileFullName.Substring(index);      if (ext == ".rar" || ext == ".zip")      {        return ext;      }      else      {        throw new Exception("The source package file is not a compress file");      }    }  }

   上述代码便是压缩文件的方法,我的测试结果如下:

   

   这是项目源文件,我要把:高效程序员的45个习惯压缩.pdf 文件进行压缩,由图可知,确实压缩成了:高效程序员的45个习惯压缩.zip 但是当你尝试去解压这个.zip文件后,你会发现解压后得到的文件夹中包含N+1层文件夹,最后的一层文件夹中能够找到我压缩的pdf文件,这点匪夷所思,有兴趣的小虎斑可以把你们的见解贴在下面的评论上,供大家参考,同时也为LZ提供个思路,谢谢!

   我示例的代码如下:

 public ActionResult Index()    {      C2Global.Architect.Common.ZipUtility zip = new C2Global.Architect.Common.ZipUtility();      zip.ZipFile(Server.MapPath("~/file/高效程序员的45个习惯.pdf"), Server.MapPath("~/file/高效程序员的45个习惯.zip"), 5, 10);      return View();    }

   程序声明:本段程序需要引用一个dll文件,这个dll文件的全名叫做:ICSharpCode.SharpZipLib.dll 小虎斑们可自行下载

   

   大家也可尝试用这个链接进行下载:http://files.cnblogs.com/files/chenwolong/ICSharpCode.SharpZipLib.zip  这是我上传至博客园的,应该可以下载,支持Net4.5框架

   关于:解压后得到的文件夹中包含N+1层文件夹的问题,欢迎大家指正,讨论,谢谢!

   @陈卧龙的博客