Download multiple files as Zip Archive File in ASP.Net using C# and VB.Net

Here Mudassar Ahmed Khan has explained with an example and attached sample code, how to download multiple files from server on single button click through GridView by creating Zip Archive File using DotNetZip Library in ASP.Net using C# and VB.Net

Referencing the DotNetZip LibraryYou will need to download the DotNetZip Library DLL using the Download Link provided below.Download DotNetZip Or your will find the DLL in the attached sample at the end of the article.Once you have the DLL you need to place the Ionic.Zip.Reduced.dll in the BIN Folder.VB.NetImports System.IOImports Ionic.ZipImports System.Collections.GenericDownloading Multiple Files selected in GridView as Zip Archive File using DotNetZipC#protected void DownloadFiles(object sender, EventArgs e){    using (ZipFile zip = new ZipFile())    {        zip.AlternateEncodingUsage = ZipOption.AsNecessary;        zip.AddDirectoryByName("Files");        foreach (GridViewRow row in GridView1.Rows)        {            if ((row.FindControl("chkSelect") as CheckBox).Checked)            {                string filePath = (row.FindControl("lblFilePath") as Label).Text;                zip.AddFile(filePath, "Files");            }        }        Response.Clear();        Response.BufferOutput = false;        string zipName = String.Format("Zip_{0}.zip", DateTime.Now.ToString("yyyy-MMM-dd-HHmmss"));        Response.ContentType = "application/zip";        Response.AddHeader("content-disposition", "attachment; filename=" + zipName);        zip.Save(Response.OutputStream);        Response.End();    }} VB.NetProtected Sub DownloadFiles(sender As Object, e As EventArgs)    Using zip As New ZipFile()        zip.AlternateEncodingUsage = ZipOption.AsNecessary        zip.AddDirectoryByName("Files")        For Each row As GridViewRow In GridView1.Rows            If TryCast(row.FindControl("chkSelect"), CheckBox).Checked Then                Dim filePath As String = TryCast(row.FindControl("lblFilePath"), Label).Text                zip.AddFile(filePath, "Files")            End If        Next        Response.Clear()        Response.BufferOutput = False        Dim zipName As String = [String].Format("Zip_{0}.zip", DateTime.Now.ToString("yyyy-MMM-dd-HHmmss"))        Response.ContentType = "application/zip"        Response.AddHeader("content-disposition", "attachment; filename=" + zipName)        zip.Save(Response.OutputStream)        Response.[End]()    End UsingEnd Sub

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