Protected Function ConvertToKB(path As Object) As String
        Dim fi As New FileInfo(Server.MapPath(path))
        Return String.Format("{0}KB", Math.Round(fi.Length / 1024, 2))
    End Function

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

        Dim files() As FileInfo = New DirectoryInfo(Server.MapPath(DataDirectory)).GetFiles
        GridView2.DataSource = files
        GridView2.DataBind()


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

        MaintainScrollPositionOnPostBack = True
    End Sub

    Protected Sub GridView2_RowDataBound(sender As Object, e As System.Web.UI.WebControls.GridViewRowEventArgs) Handles GridView2.RowDataBound
        If e.Row.RowType = DataControlRowType.DataRow Then
            Dim I As Int64
            Dim S As String = "Fred"
            I = Convert.ToInt64(e.Row.Cells(1).Text)
            S = (I / 1024).ToString & " KB"
            e.Row.Cells(1).Text = S
        End If
    End Sub

    Protected Sub GridView2_PageIndexChanging(sender As Object, e As System.Web.UI.WebControls.GridViewPageEventArgs) Handles GridView2.PageIndexChanging
        GridView2.PageIndex = e.NewPageIndex
        BindGrid()
    End Sub

    Protected Sub GridView2_RowCommand(sender As Object, e As System.Web.UI.WebControls.GridViewCommandEventArgs) Handles GridView2.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
End Class