public void BindData()
 
    {
 
 
 
        con = new SqlConnection("Initial Catalog=Northwind; Data Source=localhost; Uid=sa; pwd=;");
 
        cmd.CommandText = "select * from Employees ";
 
        cmd.Connection = con;
 
        con.Open();
 
        da = new SqlDataAdapter(cmd);
 
        da.Fill(ds);
 
        cmd.ExecuteNonQuery();
 
        GridData.DataSource = ds;
 
        GridData.DataBind();
 
    }
 
    protected void Timer1_Tick(object sender, EventArgs e)
 
    {
        Label1.Text = "Grid Refreshed at: " + DateTime.Now.ToLongTimeString();
    }

<form id="form1" runat="server">
     <asp:Label ID="Label2" runat="server" Text="This is Time, When The Full Page Load :" Font-Bold="true"></asp:Label>&nbsp;
     <asp:Label ID="MyLabel" runat="server"></asp:Label><br /><br />       
    <asp:ScriptManager ID="ScriptManager1" runat="server" />
        <div>
            <asp:Timer ID="Timer1" OnTick="Timer1_Tick" runat="server" Interval="30000">
            </asp:Timer>
        </div>
        <asp:UpdatePanel ID="UpdatePanel1" UpdateMode="Conditional" runat="server">
            <Triggers>
                <asp:AsyncPostBackTrigger ControlID="Timer1" EventName="Tick" />
            </Triggers>
            <ContentTemplate>
                <asp:Label ID="Label3" runat="server" Text="This is The Time when Only Data Grid will Referesh :" Font-Bold="true"></asp:Label>&nbsp;
                <asp:Label ID="Label1" runat="server" Text="Grid not refreshed yet."></asp:Label><br />
                <asp:Label ID="Label4" runat="server" Text="(Grid Will Referesh after Every 30 Sec)" Font-Bold="true"></asp:Label>&nbsp;
                <br /><br />
                <asp:DataGrid ID=GridData runat="server" Width="100%" GridLines="Both" HeaderStyle-BackColor="#999999" AutoGenerateColumns="false">
                    <Columns>
                        <asp:BoundColumn DataField="EmployeeID" HeaderText="Employee ID"></asp:BoundColumn>
                        <asp:BoundColumn DataField="FirstName" HeaderText="First Name"></asp:BoundColumn>
                         <asp:BoundColumn DataField="LastName" HeaderText="Last Name"></asp:BoundColumn>
                        <asp:BoundColumn DataField="City" HeaderText="City"></asp:BoundColumn>
                    </Columns>
                </asp:DataGrid>
            </ContentTemplate>
        </asp:UpdatePanel>    
    </form> 
</html>

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