You can zip a file or a folder in ASP.NET by using, ICSharpCode.SharpZipLib.Zip or other library assemblies.SharpZipLib can be downloaded from: ASP.NET examples below demonstrate how to zip files.
using ICSharpCode.SharpZipLib.Zip; using System.IO;ZipOutputStream zos = null; protected void Button1_Click(object sender, EventArgs e) { string[] pathCollection = new string[2]; PathCellction[0] = “c:\\folder1”; PathCellction[1] = “c:\\folder2”; StartZip(pathCollection, “filename”); }protected void StartZip(string[] pathCollection, string strFileName) { MemoryStream ms; Response.ContentType = “application/octet-stream”; strFileName = HttpUtility.UrlEncode(strFileName).Replace(‘+’, ‘ ‘); Response.AddHeader(“Content-Disposition”, “attachment; filename=” + strFileName + “.zip”); ms = new MemoryStream(); zos = new ZipOutputStream(ms); addZipEntry(pathCollection); ms.Close(); zos.Finish(); zos.Close(); Response.Clear(); Response.BinaryWrite(ms.ToArray()); Response.End(); }protected void addZipEntry(string[] pathCollection) { for (int i = 0; i < pathCollection.Length; i++) { string strPath = pathCollection[i]; addZipEntry(strPath, strPath.LastIndexOf("\\") + 1); } }protected void addZipEntry(string strPath, int baseIndex) { DirectoryInfo di = new DirectoryInfo(strPath); foreach (DirectoryInfo item in di.GetDirectories()) { addZipEntry(item.FullName, baseIndex); } foreach (FileInfo item in di.GetFiles()) { FileStream fs = File.OpenRead(item.FullName); byte[] buffer = new byte[fs.Length]; fs.Read(buffer, 0, buffer.Length); string strEntryName = item.FullName.Remove(0, baseIndex); ZipEntry entry = new ZipEntry(strEntryName); zos.PutNextEntry(entry); zos.Write(buffer, 0, buffer.Length); fs.Close(); } }

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