Displaying the files for a specific folder and allow the user to download them.

This is how to to list the files in a specific directory and allow the user to download the files.

ASPX:

<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" CellPadding="2"
    ForeColor="#333333" GridLines="None" AllowPaging="True">
    <Columns>
        <asp:TemplateField>
            <ItemTemplate>
                <asp:LinkButton ID="lnkdownload" runat="server" Text="Download" CommandName="Download"
                    CommandArgument='<%#Eval("FullName") +";" + Eval("Name") %>'></asp:LinkButton>
            </ItemTemplate>
        </asp:TemplateField>
        <asp:BoundField DataField="Name" HeaderText="File Name" />
        <asp:BoundField DataField="Length" HeaderText="Size (Bytes)" />
    </Columns>
    <FooterStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" />
    <RowStyle BackColor="#F7F6F3" ForeColor="#333333" />
    <PagerStyle BackColor="#284775" ForeColor="White" HorizontalAlign="Center" />
    <SelectedRowStyle BackColor="#E2DED6" Font-Bold="True" ForeColor="#333333" />
    <HeaderStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" />
    <EditRowStyle BackColor="#999999" />
    <AlternatingRowStyle BackColor="White" ForeColor="#284775" />
</asp:GridView>

VB:

Private Sub BindGrid()
     Dim DataDirectory As String = "~/Uploads"

     Dim files() As FileInfo = New DirectoryInfo(Server.MapPath(DataDirectory)).GetFiles
     GridView1.DataSource = files
     GridView1.DataBind()


 End Sub
 Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
     If Not IsPostBack Then
         BindGrid()
     End If
 End Sub

 Private Sub Downloadfile(ByVal fileName As String, ByVal FullFilePath As String)
     Response.AddHeader("Content-Disposition", "attachment; filename=" & fileName)
     Response.TransmitFile(FullFilePath)
     Response.End()
 End Sub

 Protected Sub GridView1_RowCommand(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewCommandEventArgs) Handles GridView1.RowCommand
     If e.CommandName = "Download" Then
         Dim fileInfo() As String = e.CommandArgument.ToString().Split(";")
         Dim FileName As String = fileInfo(1)
         Dim FullPath As String = fileInfo(0)
         Downloadfile(FileName, FullPath)
     End If
 End Sub

 Protected Sub GridView1_PageIndexChanging(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewPageEventArgs) Handles GridView1.PageIndexChanging
     GridView1.PageIndex = e.NewPageIndex
     BindGrid()

 End Sub

Note: the mentioned code List the files from "Uploads" directory  , and so you may need to change the name of that folder based on your website, also the code can be extended to allow the user to Dynamicly selects the directory name to list its files.