Reset CountDown Timer using ASP.Net Timer control in C# and VB.Net

Hi nauna,

Check this sample.

HTML

<asp:ScriptManager ID="ScriptManager1" runat="server">
</asp:ScriptManager>
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
    <ContentTemplate>
        <div id="dvTimer">
            <asp:Label ID="lblTimer" runat="server" Text="10:00" />
            <asp:Timer runat="server" Interval="1000" OnTick="OnTimerTick">
            </asp:Timer>
        </div>
    </ContentTemplate>
</asp:UpdatePanel>

Namespaces

C#

using System.Drawing;

VB.Net

Imports System.Drawing

Code

C#

protected void OnTimerTick(object sender, EventArgs e)
{
    int sec = 0;
    if (ViewState["Time"] == null)
    {
        ViewState["Time"] = 10;
    }
    else
    {
        sec = Convert.ToInt32(ViewState["Time"]);
        sec--;
        ViewState["Time"] = sec;
    }

    if (ViewState["Time"] != null)
    {
        lblTimer.ForeColor = Color.Black;
        lblTimer.Text = ViewState["Time"].ToString().PadLeft(2, '0') + " : 00";
    }
    if ((int)ViewState["Time"] == 1)
    {
        lblTimer.ForeColor = Color.Red;
        ViewState["Time"] = null;
    }
}

VB.Net

Protected Sub OnTimerTick(ByVal sender As Object, ByVal e As EventArgs)
    Dim sec As Integer = 0
    If ViewState("Time") Is Nothing Then
        ViewState("Time") = 10
    Else
        sec = Convert.ToInt32(ViewState("Time"))
        sec -= 1
        ViewState("Time") = sec
    End If
    If ViewState("Time") IsNot Nothing Then
        lblTimer.ForeColor = Color.Black
        lblTimer.Text = ViewState("Time").ToString().PadLeft(2, "0"c) & " : 00"
    End If
    If CInt(ViewState("Time")) = 1 Then
        lblTimer.ForeColor = Color.Red
        ViewState("Time") = Nothing
    End If
End Sub

Screenshot