ASP. NET file compression and decompression class (C)
- 2021-08-03 10:01:24
- OfStack
In this paper, the method of extracting files by asp. net C # is described. It is necessary to refer to one ICSharpCode. SharpZipLib. dll for your reference, as follows:
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> /// Author: From Grid <br> /// Modifier :sunkaixaun
/// Compress and unzip files
/// </summary>
public class ZipClass
{
/// <summary>
/// All file cache
/// </summary>
List<string> files = new List<string>();
/// <summary>
/// All empty directory caches
/// </summary>
List<string> paths = new List<string>();
/// <summary>
/// Compress a single file according to the file address
/// </summary>
/// <param name="fileToZip"> File to be compressed </param>
/// <param name="zipedFile"> Full name of compressed file </param>
/// <param name="compressionLevel"> Degree of compression, range 0-9 The larger the value, the higher the compression program </param>
/// <param name="blockSize"> Block size </param>
public void ZipFile(string fileToZip, string zipedFile, int compressionLevel, int blockSize)
{
if (!System.IO.File.Exists(fileToZip))// If the file is not found, an error is reported
{
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>
/// Compressed directory (including subdirectories and all files)
/// </summary>
/// <param name="rootPath"> Root directory to compress </param>
/// <param name="destinationPath"> Save path </param>
/// <param name="compressLevel"> Degree of compression, range 0-9 The larger the value, the higher the compression program </param>
public void ZipFileFromDirectory(string rootPath, string destinationPath, int compressLevel)
{
GetAllDirectories(rootPath);
/* while (rootPath.LastIndexOf("\\") + 1 == rootPath.Length)// Check whether the path is used with "\" End
{
rootPath = rootPath.Substring(0, rootPath.Length - 1);// If yes, remove the last "\"
}
*/
//string rootMark = rootPath.Substring(0, rootPath.LastIndexOf("\\") + 1);// The position of the current path is obtained for converting the compressed content into a relative path during compression.
string rootMark = rootPath + "\\";// The position of the current path is obtained for converting the compressed content into a relative path during compression.
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);// Open zip file
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>
/// Multi-file package download
/// </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();// With this name formatter, you can use the file name inside to 1 Some treatment. By default, it is automatically set in the zip Create the relevant folder in.
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>
/// Get all files and folders in the directory and store them in files And paths
/// </summary>
/// <param name="rootPath"> Root directory </param>
private void GetAllDirectories(string rootPath)
{
string[] subPaths = Directory.GetDirectories(rootPath);// Get all subdirectories
foreach (string path in subPaths)
{
GetAllDirectories(path);// To each 1 The one-word directory does the same thing as the root directory: find the subdirectory and store the file name of the current directory in List
}
string[] files = Directory.GetFiles(rootPath);
foreach (string file in files)
{
this.files.Add(file);// Save the full names of all files in the current directory to a file List
}
if (subPaths.Length == files.Length && files.Length == 0)// If it is an empty directory
{
this.paths.Add(rootPath);// Record an empty directory
}
}
/// <summary>
/// Extract a file ( The zip file contains subdirectories )
/// </summary>
/// <param name="zipfilepath"> The path of the file to be unzipped </param>
/// <param name="unzippath"> Extract to specified directory </param>
/// <returns> File list after extraction </returns>
public List<string> UnZip(string zipfilepath, string unzippath)
{
// Extracted list of files
List<string> unzipFiles = new List<string>();
// Check whether the output directory is marked with " \\ "End
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);
// Generate unzipped directory "When users unzip to the root directory of hard disk, they do not need to create"
if (!string.IsNullOrEmpty(directoryName))
{
Directory.CreateDirectory(directoryName);
}
if (fileName != String.Empty)
{
// If the compressed size of the file is 0 Then the file is empty , So there is no need to read and write
if (theEntry.CompressedSize == 0)
break;
// Unzip the file to the specified directory
directoryName = Path.GetDirectoryName(unzippath + theEntry.Name);
// Create the following directories and subdirectories
Directory.CreateDirectory(directoryName);
// Record exported files
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 Member
public string TransformDirectory(string name)
{
return null;
}
public string TransformFile(string name)
{
return Path.GetFileName(name);
}
#endregion
}
}