ionic zip download in .Net c#

If you want to manipulate the zip features like create,extract and update zip files in .Net. You can implement from the third party libraries DotNetZip . You need to reference the dll ionic zip in your project and import namespace Ionic.Zip in the page. 

In this example, I am adding the images and creating a zip file with the folder name called Album.

protected void btnDownload_Click(object sender, EventArgs e)
    {
       Response.Clear();
       Response.ContentType = "application/zip";
       Response.AddHeader("content-disposition", "filename=" + "Donload.zip");
        using (ZipFile zip = new ZipFile())
        {
            foreach (ListItem item in chkAlbum.Items)
            {
                if (item.Selected)
               {
                   zip.AddFile(item.Value, "Album");
               }
            }
           zip.Save(Response.OutputStream);
        }
    }   

Zip files Downloaded in browser specified path