Display list of files from nested folders in ASP.net

Here I have created sample that will help you out.I have used recursion.

HTML

<div>
    <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="false" EmptyDataText="No files uploaded">
        <Columns>
            <asp:BoundField DataField="Text" HeaderText="File Name" />
        </Columns>
    </asp:GridView>
</div>

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        string[] folders = Directory.GetDirectories(Server.MapPath("~/Uploads/"));
        List<ListItem> files = new List<ListItem>();
        files = GetFiles(folders, files);
        GridView1.DataSource = files;
        GridView1.DataBind();
    }
}

private List<ListItem> GetFiles(string[] folders, List<ListItem> files)
{
    foreach (string folder in folders)
    {
        string[] filePaths = Directory.GetFiles(folder);
        foreach (string filePath in filePaths)
        {
            files.Add(new ListItem(Path.GetFileName(filePath), filePath));
        }
        string[] ChildFolders = Directory.GetDirectories(folder);
        if (ChildFolders.Length > 0)
        {
            GetFiles(ChildFolders, files);
        }
    }
    return files;
}

Screenshot

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