error in timer tick event

having error in timer tick event 

 

<%@ Page Title="" Language="C#" MasterPageFile="~/Site.Master" AutoEventWireup="true" CodeBehind="L_PaperSet.aspx.cs" Inherits="Lib_Web.WebForm2" %> <asp:Content ID="Content1" ContentPlaceHolderID="HeadContent" runat="server">     <style type="text/css">         .style7         {             width: 100%;         }         .style8         {             width: 228px;         }     style> </asp:Content> <asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">     <table class="style7">         <tr>             <td class="style8">                  </td>             <td>                 <asp:ScriptManager ID="ScriptManager1" runat="server">                 </asp:ScriptManager>                 <asp:UpdatePanel ID="UpdatePanel1" runat="server">                     <ContentTemplate>                           <asp:Timer ID="Timer1" runat="server" ontick="Timer1_Tick">                         </asp:Timer>                         <asp:Image ID="Image1" runat="server" />                     </ContentTemplate>                    </asp:UpdatePanel>               </td>         </tr>         <tr>             <td class="style8">                  </td>             <td>                  </td>         </tr>     </table> </asp:Content>

 

using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.UI; using System.Web.UI.WebControls;   namespace Lib_Web {     public partial class WebForm2 : System.Web.UI.Page     {         protected void Page_Load(object sender, EventArgs e)         {             if (!IsPostBack)             {                 NewMethod();               }         }           protected void Timer1_Tick(object sender, EventArgs e)         {             NewMethod();         }           private void NewMethod()         {             Random rand = new Random();             int i = rand.Next(1, 4);             Image1.ImageUrl = "~/L_pics/" + i.ToString() + ".jpg";         }     } }

Description: An error occurred during the compilation of a resource required to service this request. Please review the following specific error details and modify your source code appropriately. 
 
Compiler Error Message: CS1061: 'ASP.l_paperset_aspx' does not contain a definition for 'Timer1_Tick' and no extension method 'Timer1_Tick' accepting a first argument of type 'ASP.l_paperset_aspx' could be found (are you missing a using directive or an assembly reference?)
 
Source Error:
 

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