Using countdown timer on gridview row

hi Here is demo code u can use it and manipulate vb code to C#
may it will help.

<div>     <asp:ScriptManager ID="ScriptManager1" runat="server">     asp:ScriptManager> div> <asp:UpdatePanel ID="UpdatePanel1" runat="server">     <ContentTemplate>         <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False">             <Columns>                 <asp:TemplateField>                     <ItemTemplate>                         <asp:ImageButton ID="ImageButton1" runat="server" />                     ItemTemplate>                 asp:TemplateField>             Columns>         asp:GridView>         <asp:Timer ID="Timer1" runat="server" Interval="1000">         asp:Timer>         <asp:Label ID="Label1" runat="server" Text="Label">asp:Label>     ContentTemplate>     <Triggers>         <asp:AsyncPostBackTrigger ControlID="GridView1" EventName="RowCommand" />         <asp:AsyncPostBackTrigger ControlID="Timer1" EventName="Tick" />     Triggers> asp:UpdatePanel>

Code-Behind

Dim lst As New List(Of String)     Protected Sub GridView1_RowCommand(sender As Object, e As System.Web.UI.WebControls.GridViewCommandEventArgs) Handles GridView1.RowCommand         Label1.Text = DateTime.Now     End Sub      Protected Sub Page_Load(sender As Object, e As System.EventArgs) Handles Me.Load         If Not IsPostBack Then             If IsNothing(Session("lst")) Then                 Session("lst") = lst             End If             GridView1.DataSource = lst             GridView1.DataBind()         End If     End Sub      Protected Sub Timer1_Tick(sender As Object, e As System.EventArgs) Handles Timer1.Tick         lst = Session("lst")         lst.Add(DateTime.Now.ToString())         GridView1.DataSource = lst         GridView1.DataBind()     End Sub