求高手解答一下


<%@ Page Language="C#" AutoEventWireup="true" CodeFile="xiugai.aspx.cs" Inherits="xiugai" %>
<%@ Import Namespace="System.Data.SqlClient" %>
<%@ Import Namespace="System.Data" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<%
          string strConn = System.Configuration.ConfigurationManager.AppSettings["DSN"];
          SqlConnection conn = new SqlConnection(strConn);
          conn.Open();
          SqlCommand cmd = new SqlCommand("select * from Users", conn);
          SqlDataReader reader = cmd.ExecuteReader();
          
          
           %>
</head><body>
<div align="center">
  <table width="200" border="1">
    <tr>
      <td colspan="2"><div align="center">修改用户</div></td>
    </tr>
    <tr>
      <td colspan="2" style="text-align: left">
      <%
          
         
              
              while (reader.Read())
                {
                    string URL = "<a href=EditUser.aspx?id=" + reader.GetString("id") + ">编辑</a>";
                }
              Response.Write("<br>");
          
          reader.Close();
          conn.Close();
           %>
      </td>
    </tr>
  </table>
</div>
</body>
</html>这一句有问题：string URL = "<a href=EditUser.aspx?id=" + reader.GetString("id") + ">编辑</a>";