private void DownloadFile(string fname, bool forceDownload)
    {
        string path = MapPath("upload") + "\\" + fname;
        string name = Path.GetFileName(path);

        if (forceDownload)
        {
            Response.AppendHeader("content-disposition", "attachment; filename=" + name);
        }
        Response.WriteFile(path);
        Response.End();
    }
 protected void GridView1_RowCommand(object sender, GridViewCommandEventArgs e)
    {
        if(e.CommandName=="xyz")
        {
            string id=e.CommandArgument.ToString();
            Response.Redirect("nextpage.aspx?name=" + id);
        }





        if (e.CommandName == "mahua")
        {
            string picpath = Convert.ToString(e.CommandArgument);
            int len = picpath.Length;
            picname = picpath.Substring(9, len - 9);
            DownloadFile(picname, true);
        }

//name of the folder/is upload////////////