ASP.NET 文件压缩解压类（C#）

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using ICSharpCode.SharpZipLib.Zip;
using System.IO;
using ICSharpCode.SharpZipLib.Checksums;
using System.Web;
namespace Mvc51Hiring.Common.Tool
{
/// <summary> <br>  /// 作者：来自网格<br>  /// 修改人:sunkaixaun
/// 压缩和解压文件 
/// </summary> 
public class ZipClass
{
/// <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> 
/// 压缩单个文件根据文件地址
/// </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;
// 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 = 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> 
/// 多文件打包下载
/// </summary> 
public void DwonloadZip(string[] filePathList, string zipName)
{
MemoryStream ms = new MemoryStream();
byte[] buffer = null;
var context = HttpContext.Current;
using (ICSharpCode.SharpZipLib.Zip.ZipFile file = ICSharpCode.SharpZipLib.Zip.ZipFile.Create(ms))
{
file.BeginUpdate();
file.NameTransform = new MyNameTransfom();//通过这个名称格式化器，可以将里面的文件名进行一些处理。默认情况下，会自动根据文件的路径在zip中创建有关的文件夹。
foreach (var it in filePathList)
{
file.Add(context.Server.MapPath(it));
}
file.CommitUpdate();
buffer = new byte[ms.Length];
ms.Position = 0;
ms.Read(buffer, 0, buffer.Length);
}
context.Response.AddHeader("content-disposition", "attachment;filename=" + zipName);
context.Response.BinaryWrite(buffer);
context.Response.Flush();
context.Response.End();
}
/// <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)
break;
//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 class MyNameTransfom : ICSharpCode.SharpZipLib.Core.INameTransform
{
#region INameTransform 成员
public string TransformDirectory(string name)
{
return null;
}
public string TransformFile(string name)
{
return Path.GetFileName(name);
}
#endregion
}
}