Member Avatar for ringo_tech

Hi there,
I have a database which contains the paths of different files, what I want to do is to store the paths in an array to create an array of paths then download these files with one click.

How to do that?
please help

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  • Latest Post Latest Post by pritaeas

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Two practical patterns for "one-click" download of many files were implied in this thread: zip everything server-side and send a single ZIP, or fetch files client-side and build the ZIP in the browser. was right to point out looping the list — but common gaps under that surface cause "nothing" to be delivered. The checklist at the end helps avoid those traps; below are compact, practical examples and notes.

Server-side (robust for large sets): build the archive on the server and stream it back. This C# MVC-style example uses the BCL ZipArchive and streams each file into the archive so you avoid re-reading names manually:

public ActionResult DownloadZip(IEnumerable<int> ids)
{
    var paths = GetPathsFromDatabase(ids); // absolute server paths
    var ms = new MemoryStream();
    using (var archive = new ZipArchive(ms, ZipArchiveMode.Create, true))
    {
        foreach (var p in paths)
        {
            if (!System.IO.File.Exists(p)) continue;
            var entry = archive.CreateEntry(Path.GetFileName(p));
            using (var es = entry.Open())
            using (var fs = System.IO.File.OpenRead(p))
                fs.CopyTo(es);
        }
    }
    ms.Position = 0;
    return File(ms, "application/zip", "files.zip");
}

Client-side (good for smaller files, avoids server CPU): fetch each file as a blob, add to a JSZip instance, then generate and download the zip. See JSZip docs for examples: JSZip.

Checklist / troubleshooting (why people often "get nothing"):

  • Ensure the list of paths is available at download time (persist in Session/ViewState or rebind before the click).
  • Verify the app pool user can read those paths and the paths are correct (virtual vs absolute vs UNC).
  • Confirm controls/IDs used to read paths actually contain the values on postback.
  • Avoid creating huge in-memory zips for very large files; prefer on-disk streaming or a streaming library.
  • Use framework file-return helpers (FileResult / FileStreamResult) instead of brittle response-abort calls.

If posts the exact fix they found, it will help others who hit the same subtle postback or permission issue. For compression details see Microsoft docs on ZipArchive: ZipArchive.

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Member Avatar for pritaeas

What do you have so far? What do you need help with?

Member Avatar for ringo_tech

how to download multiple files with one click, I have the paths in an array

Member Avatar for pritaeas

Loop the array, get the files.

Member Avatar for ringo_tech

i did that but got nothing

this is the code

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        If Not IsPostBack Then
            Dim i As Integer = 0
            Dim pp() As String = {"F:\New folder (2)\1. pdf", "F:\New folder (2)\2.txt", "F:\New folder (2)\3.docx"}
            Dim files As New List(Of ListItem)()
            For Each filePath As String In pp
                files.Add(New ListItem(pp(i)))
                i = i + 1
            Next
            GridView1.DataSource = files
            GridView1.DataBind()
        End If
    End Sub

    Protected Sub btnDownload_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnDownload.Click
        Using zip As New ZipFile()
            zip.AlternateEncodingUsage = ZipOption.AsNecessary
            zip.AddDirectoryByName("files")
            For Each row As GridViewRow In GridView1.Rows
                Dim filePath As String = TryCast(row.FindControl("lblFilePath"), Label).Text
                zip.AddFile(filePath, "files")
            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 Using
    End Sub
Member Avatar for ringo_tech

solved
thanks to myself

Member Avatar for pritaeas

Care to share your solution, to help others in the future?

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