[Solved] LinkButton inside ASP.Net GridView getting hidden after update record

hello

i have problem after update the data from Grideview, wen i press edit then press update the file download going my code.

when i insert data  with fileupload everything good.

then  when i try edit something same data like i edit the txtname or country without change the file download.

when i press update, the download file going/removed.

HTML

<asp:TemplateField HeaderText="ﻣﺮﻓﻘﺎت">
    <ItemTemplate>
        <asp:LinkButton ID="lnkDownload" runat="server" Text="Download"
            OnClick="DownloadFile" CommandArgument='<%# Eval("Id") %>' Visible='<%#!string.IsNullOrEmpty(Eval("Namefile").ToString()) ? true : false %>'>  </asp:LinkButton>
    </ItemTemplate>
    <EditItemTemplate>
        <asp:FileUpload ID="fuFile" runat="server" />
    </EditItemTemplate>
    <ControlStyle Width="100px" />
    <ItemStyle HorizontalAlign="Center" Width="70px" />
</asp:TemplateField>

protected void OnRowUpdating(object sender, GridViewUpdateEventArgs e)
{
    string UserHostName = HttpContext.Current.Request.UserHostName;
    string UserHostip = System.Net.Dns.GetHostName();
    string usernamemove = this.Page.User.Identity.Name;

    GridViewRow row = GridView1.Rows[e.RowIndex];
    int id = Convert.ToInt32(GridView1.DataKeys[e.RowIndex].Values[0]);
    FileUpload FileUpload1 = row.FindControl("fuFile") as FileUpload;
    string fileName = Path.GetFileName(FileUpload1.PostedFile.FileName);


    string contentType = "";
    byte[] bytes = null;
    if (FileUpload1.HasFile)
    {
        contentType = FileUpload1.PostedFile.ContentType;
        using (Stream fs = FileUpload1.PostedFile.InputStream)
        {
            using (BinaryReader br = new BinaryReader(fs))
            {
                bytes = br.ReadBytes((Int32)fs.Length);
            }
        }
    }

    var massage = (row.FindControl("txtName") as TextBox).Text.Trim();

    var note = (row.FindControl("txtCountry") as TextBox).Text.Trim();

    using (var con = new SqlConnection(str))
    {
        var query =
            "UPDATE Table_fileupload SET  others1 = @others1,totaltimespplus = @totaltimespplus,noteme = @noteme,note = @note, massage = @massage, Namefile = @Namefile, ContentType = @ContentType, backupmyfile = @backupmyfile  WHERE id = @Id";
        using (var cmd = new SqlCommand(query))

        {
            cmd.Connection = con;
            cmd.Parameters.AddWithValue("@Id", id);
            cmd.Parameters.AddWithValue("@Namefile", fileName);
            cmd.Parameters.AddWithValue("@ContentType", contentType);
            cmd.Parameters.AddWithValue("@backupmyfile", bytes == null ? new byte[] { } : bytes);

            cmd.Parameters.AddWithValue("@massage", massage);
            cmd.Parameters.AddWithValue("@note", note);

            // التتبع
            cmd.Parameters.AddWithValue("@others1", usernamemove);
            cmd.Parameters.AddWithValue("@totaltimespplus", Convert.ToDateTime(DateTime.Now.ToLongTimeString()));

            cmd.Parameters.AddWithValue("@noteme", "(تعديل)");

            cmd.Parameters.AddWithValue("@machineName", GetComputerName(Request.UserHostAddress));
            cmd.Parameters.AddWithValue("@localIP", UserHostName);

            con.Open();
            cmd.ExecuteNonQuery();
            con.Close();
        }
    }

    GridView1.EditIndex = -1;
    BindGrid2SP();
    Response.Redirect(Request.Url.AbsoluteUri);
}