文件的压缩和解压缩

我在做项目的时候需要将文件进行压缩和解压缩，于是就从http://www.icsharpcode.net/下载了关于压缩和解压缩的源码，但是下载下来后，面对这么多的代码，一时不知如何下手。只好耐下心来，慢慢的研究，总算找到了门路。针对自己的需要改写了文件压缩和解压缩的两个类，分别为ZipClass和UnZipClass。其中碰到了不少困难，就决定写出来压缩和解压的程序后，一定把源码贴出来共享，让首次接触压缩和解压缩的朋友可以少走些弯路。下面就来解释如何在C#里用http://www.icsharpcode.net/下载的SharpZipLib进行文件的压缩和解压缩。



    首先需要在项目里引用SharpZipLib.dll。然后修改其中的关于压缩和解压缩的类。实现源码如下：



 /// <summary>

 /// 压缩文件

 /// </summary>



using System;

using System.IO;



using ICSharpCode.SharpZipLib.Checksums;

using ICSharpCode.SharpZipLib.Zip;

using ICSharpCode.SharpZipLib.GZip;



namespace Compression

{

 public class ZipClass

 {

 

  public void ZipFile(string FileToZip, string ZipedFile ,int CompressionLevel, int BlockSize)

  {

   //如果文件没有找到，则报错

   if (! System.IO.File.Exists(FileToZip)) 

   {

    throw new System.IO.FileNotFoundException("The specified file " + FileToZip + " could not be found. Zipping aborderd");

   }

  

   System.IO.FileStream StreamToZip = new System.IO.FileStream(FileToZip,System.IO.FileMode.Open , System.IO.FileAccess.Read);

   System.IO.FileStream ZipFile = System.IO.File.Create(ZipedFile);

   ZipOutputStream ZipStream = new ZipOutputStream(ZipFile);

   ZipEntry ZipEntry = new ZipEntry("ZippedFile");

   ZipStream.PutNextEntry(ZipEntry);

   ZipStream.SetLevel(CompressionLevel);

   byte[] buffer = new byte[BlockSize];

   System.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(System.Exception ex)

   {

    throw ex;

   }

   ZipStream.Finish();

   ZipStream.Close();

   StreamToZip.Close();

  }

 

  public void ZipFileMain(string[] args)

  {

   string[] filenames = Directory.GetFiles(args[0]);

  

   Crc32 crc = new Crc32();

   ZipOutputStream s = new ZipOutputStream(File.Create(args[1]));

  

   s.SetLevel(6); // 0 - store only to 9 - means best compression

  

   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;

   

    // set Size and the crc, because the information

    // about the size and crc should be stored in the header

    // if it is not set it is automatically written in the footer.

    // (in this case size == crc == -1 in the header)

    // Some ZIP programs have problems with zip files that don't store

    // the size and crc in the header.

    entry.Size = fs.Length;

    fs.Close();

   

    crc.Reset();

    crc.Update(buffer);

   

    entry.Crc  = crc.Value;

   

    s.PutNextEntry(entry);

   

    s.Write(buffer, 0, buffer.Length);

   

   }

  

   s.Finish();

   s.Close();

  }

 }

}



现在再来看看解压文件类的源码



 /// <summary>

 /// 解压文件

 /// </summary>



using System;

using System.Text;

using System.Collections;

using System.IO;

using System.Diagnostics;

using System.Runtime.Serialization.Formatters.Binary;

using System.Data;



using ICSharpCode.SharpZipLib.BZip2;

using ICSharpCode.SharpZipLib.Zip;

using ICSharpCode.SharpZipLib.Zip.Compression;

using ICSharpCode.SharpZipLib.Zip.Compression.Streams;

using ICSharpCode.SharpZipLib.GZip;



namespace DeCompression

{

 public class UnZipClass

 {   

  public void UnZip(string[] args)

  {

   ZipInputStream s = new ZipInputStream(File.OpenRead(args[0]));

  

   ZipEntry theEntry;

   while ((theEntry = s.GetNextEntry()) != null) 

   {

   

          string directoryName = Path.GetDirectoryName(args[1]);

    string fileName      = Path.GetFileName(theEntry.Name);

   

    //生成解压目录

    Directory.CreateDirectory(directoryName);

   

    if (fileName != String.Empty) 

    {   

     //解压文件到指定的目录

     FileStream streamWriter = File.Create(args[1]+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();

  }

 }

}



    有了压缩和解压缩的类以后，就要在窗体里调用了。怎么？是新手，不会调用？Ok,接着往下看如何在窗体里调用。



    首先在窗体里放置两个命令按钮（不要告诉我你不会放啊~），然后编写以下源码



/// <summary>

 /// 调用源码

 /// </summary>



      private void button2_Click_1(object sender, System.EventArgs e)

  {

   string []FileProperties=new string[2];

   FileProperties[0]="C:\\unzipped\\";//待压缩文件目录

   FileProperties[1]="C:\\zip\\a.zip";  //压缩后的目标文件

   ZipClass Zc=new ZipClass();

   Zc.ZipFileMain(FileProperties);

  }



     private void button2_Click(object sender, System.EventArgs e)

  {

   string []FileProperties=new string[2];

   FileProperties[0]="C:\\zip\\test.zip";//待解压的文件

   FileProperties[1]="C:\\unzipped\\";//解压后放置的目标目录

   UnZipClass UnZc=new UnZipClass();

   UnZc.UnZip(FileProperties);

  }



    好了，到此为止，如何压缩和解压缩的类都已经完成了，需要的朋友直接拿走调吧。