【解決方法】ASP.NET とデータベースを使用してダウンロード リンクをクリックすると、pdf ファイルが開きます

problem is file is downloaded but not open in new form.

私が試したこと：

protected void DownloadFile(object sender, EventArgs e)
        {
          //  string filePath = (sender as LinkButton).CommandArgument;
            int id = int.Parse((sender as LinkButton).CommandArgument);
            byte[] bytes;
            string fileName, contentType;
            string constr = ConfigurationManager.ConnectionStrings["conn"].ConnectionString;
            using (SqlConnection con = new SqlConnection(constr))
            {
                using (SqlCommand cmd = new SqlCommand())
                {
                    cmd.CommandText = "select Name,FileName,ContentType,Data from tblFiles where Id=@Id";
                    cmd.Parameters.AddWithValue("@Id", id);
                    cmd.Connection = con;
                    con.Open();
                    using (SqlDataReader sdr = cmd.ExecuteReader())
                    {
                        sdr.Read();
                        bytes = (byte[])sdr["Data"];
                        contentType = sdr["ContentType"].ToString();
                        fileName = sdr["Name"].ToString();
                    }
                    con.Close();
                }
            }
            Response.Clear();
            Response.Buffer = true;
            Response.Charset = "";
            Response.Cache.SetCacheability(HttpCacheability.NoCache);
            Response.ContentType = "application/pdf";
            Response.AppendHeader("Content-Disposition", "attachment; filename=" + fileName);

            //Response.ContentType = ContentType;
            //Response.AppendHeader("Content-Disposition", "attachment; filename=" + Path.GetFileName(filePath));
            //Response.WriteFile(filePath);
            //Response.End();

            Response.BinaryWrite(bytes);            
            Response.End();

        //{
        //    String strConnString = System.Configuration.ConfigurationManager.ConnectionStrings["conn"].ConnectionString;
        //    LinkButton lnkbtn = sender as LinkButton;
        //    GridViewRow gvrow = lnkbtn.NamingContainer as GridViewRow;
        //    int fileid = Convert.ToInt32(GrvImageFiles.DataKeys[gvrow.RowIndex].Value.ToString());
        //  //  string name, type;
        //    using (SqlConnection con = new SqlConnection(strConnString))
        //    {
        //        using (SqlCommand cmd = new SqlCommand())
        //        {
        //            cmd.CommandText = "select Name,FileName, ContentType,Data from tblFiles where Id=@Id";
        //            cmd.Parameters.AddWithValue("@id", fileid);
        //            cmd.Connection = con;
        //            con.Open();
        //            SqlDataReader dr = cmd.ExecuteReader();
        //            if (dr.Read())
        //            {
        //                Response.ContentType = dr["FileType"].ToString();
        //                Response.AddHeader("Content-Disposition", "attachment;filename=\"" + dr["FileName"] + "\"");
        //                Response.BinaryWrite((byte[])dr["FileData"]);
        //                Response.End();
        //            }
        //        }
        //    }

     //2.     //string filePath = (sender as LinkButton).CommandArgument;
            //Response.ContentType = ContentType;
            //Response.AppendHeader("Content-Disposition", "attachment; filename=" + Path.GetFileName(filePath));
            //Response.WriteFile(filePath);
            //Response.End();


        }