用ASP.Net实现文件的在线压缩和解压缩

　　我们经常会遇到批量上传的问题，也会遇到将某个目录下所有文件都上传到服务器上的问题。那么，如何解决此类问题呢？以前的技术一般采用ActiveX等方式，这里笔者采用SharpZlib来实现，听说VS2005已有压缩和解压缩的解决方案，笔者还没有时间用VS2005，所以就只好使用VS2003 + SharpZlib来解决问题了。

　　1、首先从这里下载0.84版本的SharpZlib源码及示例码。
　　2、下载下来之后你发现它没有VS2003的解决方案文件，没有关系。你可以自己建立，首先新建一个ZipUnzip的解决方案，然后，将上面经过解压缩之后的所有文件及目录COPY到你的解决方案所在的目录下。
　　3、在VS2003解决方案资源管理器（一般是在右上方中部点的位置）中点击显示所有文件按钮，然后可以见到很多“虚”的图标、文件及文件夹等，可以一次选择它们，然后包含进项目中。
　　4、编译，最好使用Release选项，编译完成之后你可以在\bin\Release\看到ZipUnzip.dll的类了。如果你编译时报错，说什么AssemblyKeyFile之类的，你可以使用强命名工具新建一个，也可以将AssemblyInfo.cs中[assembly: AssemblyKeyFile("。。。。。")]改成:[assembly: AssemblyKeyFile("")]  (不推荐这样做)。
　　5、新建一个WEBFORM项目，添加ZipUnzip.dll类的引用，然后添加如下文件及内容：

// ------------------------------------------
// 1. AttachmentUnZip.cs
// ------------------------------------------
using System;
using System.IO;
using ICSharpCode.SharpZipLib.Zip;
using ICSharpCode.SharpZipLib.GZip;
using ICSharpCode.SharpZipLib.BZip2;
using ICSharpCode.SharpZipLib.Checksums;
using ICSharpCode.SharpZipLib.Zip.Compression;
using ICSharpCode.SharpZipLib.Zip.Compression.Streams;

namespace WebZipUnzip
{
 public class AttachmentUnZip
 {
  public AttachmentUnZip()
  {  
  }
  public static void UpZip(string zipFile)
  {
   string []FileProperties=new string[2];
   FileProperties[0]=zipFile;//待解压的文件
   FileProperties[1]=zipFile.Substring(0,zipFile.LastIndexOf("\\")+1);//解压后放置的目标目录
   UnZipClass UnZc=new UnZipClass();
   UnZc.UnZip(FileProperties);
  }
 }
}

// ---------------------------------------------
// 2. UnZipClass.cs
// ---------------------------------------------

using System;
using System.IO;
using ICSharpCode.SharpZipLib.Zip;
using ICSharpCode.SharpZipLib.GZip;
using ICSharpCode.SharpZipLib.BZip2;
using ICSharpCode.SharpZipLib.Checksums;
using ICSharpCode.SharpZipLib.Zip.Compression;
using ICSharpCode.SharpZipLib.Zip.Compression.Streams;

namespace WebZipUnzip
{
 public class UnZipClass
 {  
  /// <summary>
  /// 解压文件
  /// </summary>
  /// <param name="args">包含要解压的文件名和要解压到的目录名数组</param>
  public void UnZip(string[] args)
  {
   ZipInputStream s = new ZipInputStream(File.OpenRead(args[0]));
   try
   {   
    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]+fileName);

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();
   }
   catch(Exception eu)
   {
    throw eu;
   }
   finally
   {
    s.Close();
   }

}//end UnZip

public static bool UnZipFile(string file, string dir)
  {
   try
   {
    if (!Directory.Exists(dir))
     Directory.CreateDirectory(dir);
    string fileFullName = Path.Combine(dir,file);
    ZipInputStream s = new ZipInputStream(File.OpenRead( fileFullName ));

ZipEntry theEntry;
    while ((theEntry = s.GetNextEntry()) != null)
    {
     string directoryName = Path.GetDirectoryName(theEntry.Name);
     string fileName = Path.GetFileName(theEntry.Name);

if (directoryName != String.Empty)
      Directory.CreateDirectory( Path.Combine(dir, directoryName));

if (fileName != String.Empty)
     {
      FileStream streamWriter = File.Create( Path.Combine(dir,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();
    return true;
   }
   catch (Exception)
   {
    throw;
   }
  }

}//end UnZipClass
}

// ----------------------------------------------
// 3. ZipClass.cs
// ----------------------------------------------
using System;
using System.IO;
using ICSharpCode.SharpZipLib.Zip;
using ICSharpCode.SharpZipLib.GZip;
using ICSharpCode.SharpZipLib.BZip2;
using ICSharpCode.SharpZipLib.Checksums;
using ICSharpCode.SharpZipLib.Zip.Compression;
using ICSharpCode.SharpZipLib.Zip.Compression.Streams;

namespace WebZipUnzip
{
 /// <summary>
 /// 压缩文件
 /// </summary>
 public class ZipClass
 {
  public void ZipFile(string FileToZip, string ZipedFile ,int CompressionLevel, int BlockSize,string password)
  {
   //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]);
   string[] filenames = new string[]{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();
  }
 }
}

// ---------------------------------------------
// 4. WebForm1.aspx
// ---------------------------------------------
  <%@ Page language="c#" Codebehind="WebForm1.aspx.cs" AutoEventWireup="false" Inherits="WebZipUnzip.WebForm1" %> 
<META content="Microsoft Visual Studio .NET 7.1" name=GENERATOR>
<META content=C# name=CODE_LANGUAGE>
<META content=JavaScript name=vs_defaultClientScript>
<META content=http://schemas.microsoft.com/intellisense/ie5 name=vs_targetSchema>
<FORM id=Form1 method=post runat="server"><?xml:namespace prefix = asp /><asp:Button id=Button1 style="Z-INDEX: 101; LEFT: 56px; POSITION: absolute; TOP: 64px" runat="server" Text="压缩"></asp:Button><asp:Button id=Button2 style="Z-INDEX: 102; LEFT: 112px; POSITION: absolute; TOP: 64px" runat="server" Text="解压"></asp:Button><INPUT id=File1 style="Z-INDEX: 103; LEFT: 32px; POSITION: absolute; TOP: 24px" type=file name=File1 runat="server"> </FORM></BODY></HTML>

//-------------------------------------------
// 5.WebForm1.aspx.cs
//-------------------------------------------

using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.IO;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;

namespace WebZipUnzip
{
 /// <summary>
 /// Summary description for WebForm1.
 /// </summary>
 public class WebForm1 : System.Web.UI.Page
 {
  protected System.Web.UI.WebControls.Button Button1;
  protected System.Web.UI.HtmlControls.HtmlInputFile File1;
  protected System.Web.UI.WebControls.Button Button2;

private void Page_Load(object sender, System.EventArgs e)
  {
   // Put user code to initialize the page here
  }

#region Web Form Designer generated code
  override protected void OnInit(EventArgs e)
  {
   //
   // CODEGEN: This call is required by the ASP.NET Web Form Designer.
   //
   InitializeComponent();
   base.OnInit(e);
  }

/// <summary>
  /// Required method for Designer support - do not modify
  /// the contents of this method with the code editor.
  /// </summary>
  private void InitializeComponent()
  {   
   this.Button1.Click += new System.EventHandler(this.Button1_Click);
   this.Button2.Click += new System.EventHandler(this.Button2_Click);
   this.Load += new System.EventHandler(this.Page_Load);

}
  #endregion

#region 压缩
  private void Button1_Click(object sender, System.EventArgs e)
  {
   string []FileProperties=new string[2];  
   string fullName=this.File1.PostedFile.FileName;//C:\test\a.txt
   string destPath=System.IO.Path.GetDirectoryName(fullName);//C:\test
   //待压缩文件
   FileProperties[0]=fullName;

//压缩后的目标文件
   FileProperties[1]= destPath +"\\"+ System.IO.Path.GetFileNameWithoutExtension(fullName) + ".zip";
   ZipClass Zc=new ZipClass();
   Zc.ZipFileMain(FileProperties);

//删除压缩前的文件
   System.IO.File.Delete(fullName);
  }

#endregion

#region 解压
  private void Button2_Click(object sender, System.EventArgs e)
  {
   string fullName=this.File1.PostedFile.FileName;//C:\test\a.zip
   //解压文件
   //AttachmentUnZip.UpZip(fullName);

//   string[] FileProperties = new string[2];
//   FileProperties[0] = fullName;//待解压的文件
//   FileProperties[1] = System.IO.Path.GetDirectoryName(fullName);//解压后放置的目标目录
//   UnZipClass UnZc=new UnZipClass();
//   UnZc.UnZip(FileProperties);
   string dir = System.IO.Path.GetDirectoryName(fullName);
   string fileName = System.IO.Path.GetFileName(fullName);
   UnZipClass.UnZipFile(fileName, dir);
  }
  #endregion
 }
}

　　OK! 试试看。

　　此方案解决了文件名中文字的问题，目录解压缩问题。
　　至于整个文件夹批量上传并压缩成一个WINZIP压缩包的问题，没有时间解决了，各位如有解决方案，不妨共享一下。