How to zip & extract files

 You can use this ZipManager class for zipping files & unzipping.


using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Net;
using System.IO;
using ICSharpCode.SharpZipLib.Zip;

namespace WebApplication1.Compress
{
    public class ZipManager
    {
        private static void ZipFiles(string inputFolderPath, string outputPathAndFile, string password)
        {
            ArrayList ar = GenerateFileList(inputFolderPath); // generate file list
            int TrimLength = (Directory.GetParent(inputFolderPath)).ToString().Length;
            // find number of chars to remove     // from orginal file path
            TrimLength += 1; //remove '\'
            FileStream ostream;
            byte[] obuffer;
            string outPath = inputFolderPath + @"\" + outputPathAndFile;
            ZipOutputStream oZipStream = new ZipOutputStream(File.Create(outPath)); // create zip stream
            if (password != null && password != String.Empty)
                oZipStream.Password = password;
            oZipStream.SetLevel(9); // maximum compression
            ZipEntry oZipEntry;
            foreach (string Fil in ar) // for each file, generate a zipentry
            {
                oZipEntry = new ZipEntry(Fil.Remove(0, TrimLength));
                oZipStream.PutNextEntry(oZipEntry);

                if (!Fil.EndsWith(@"/")) // if a file ends with '/' its a directory
                {
                    ostream = File.OpenRead(Fil);
                    obuffer = new byte[ostream.Length];
                    ostream.Read(obuffer, 0, obuffer.Length);
                    oZipStream.Write(obuffer, 0, obuffer.Length);
                }
            }
            oZipStream.Finish();
            oZipStream.Close();
        }//code for zipping files


        private static ArrayList GenerateFileList(string Dir)
        {
            ArrayList fils = new ArrayList();
            bool Empty = true;
            foreach (string file in Directory.GetFiles(Dir)) // add each file in directory
            {
                fils.Add(file);
                Empty = false;
            }

            if (Empty)
            {
                if (Directory.GetDirectories(Dir).Length == 0)
                // if directory is completely empty, add it
                {
                    fils.Add(Dir + @"/");
                }
            }

            foreach (string dirs in Directory.GetDirectories(Dir)) // recursive
            {
                foreach (object obj in GenerateFileList(dirs))
                {
                    fils.Add(obj);
                }
            }
            return fils; // return file list
        }//to get folder files

        private void UnZipFiles(Stream stream, string outputFolder)
        {
            //ZipInputStream s = new ZipInputStream(File.OpenRead(zipPathAndFile));
            ZipInputStream s = new ZipInputStream(stream);

            ZipEntry theEntry;
            string tmpEntry = String.Empty;
            while ((theEntry = s.GetNextEntry()) != null)
            {
                string directoryName = outputFolder;
                string fileName = Path.GetFileName(theEntry.Name);
                // create directory
                if (directoryName != "")
                {
                    Directory.CreateDirectory(directoryName);
                }
                if (fileName != String.Empty)
                {
                    if (theEntry.Name.IndexOf(".ini") < 0)
                    {
                        string fullPath = directoryName + "\\" + theEntry.Name;
                        fullPath = fullPath.Replace("\\ ", "\\");
                        string fullDirPath = Path.GetDirectoryName(fullPath);
                        if (!Directory.Exists(fullDirPath)) Directory.CreateDirectory(fullDirPath);
                        FileStream streamWriter = File.Create(fullPath);
                        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();
        }

        public static void ZipFiles(string inputFolderPath, string outputFolderPath,string filenameWithExtension, string password)
        {
            if (Directory.Exists(outputFolderPath))//if folder exists delete and recreate it
            {
                DirectoryInfo ifo = new DirectoryInfo(outputFolderPath);
                ifo.Delete(true);
            }

            Directory.CreateDirectory(outputFolderPath);// create folder for lecturer
            ZipFiles(outputFolderPath, filenameWithExtension, password);//zip the crearted folder
        }

        public static void UnZipFiles(string zipPathAndFile, string outputFolder, string password, bool deleteZipFile)
        {
            ZipInputStream s = new ZipInputStream(File.OpenRead(zipPathAndFile));
            if (password != null && password != String.Empty)
                s.Password = password;
            ZipEntry theEntry;
            string tmpEntry = String.Empty;
            while ((theEntry = s.GetNextEntry()) != null)
            {
                string directoryName = outputFolder;
                string fileName = Path.GetFileName(theEntry.Name);
                // create directory
                if (directoryName != "")
                {
                    Directory.CreateDirectory(directoryName);
                }
                if (fileName != String.Empty)
                {
                    if (theEntry.Name.IndexOf(".ini") < 0)
                    {
                        string fullPath = directoryName + "\\" + theEntry.Name;
                        fullPath = fullPath.Replace("\\ ", "\\");
                        string fullDirPath = Path.GetDirectoryName(fullPath);
                        if (!Directory.Exists(fullDirPath)) Directory.CreateDirectory(fullDirPath);
                        FileStream streamWriter = File.Create(fullPath);
                        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();
            if (deleteZipFile)
                File.Delete(zipPathAndFile);
        }

       
    }
}


For Zipping you can call as shown below.
 Compress.ZipManager.ZipFiles("D:/TestFiles/", "D:/TestBackup/", "Backup1.zip", "");

For unzipping
/*unzipping files*/
Compress.ZipManager.UnZipFiles("D:/TestBackup/Control_demo.zip", "D:/TestBackup/", "sahan", false);

You have to download
ICSharpCode.SharpZipLib