ALTER DATABASE ForTest SET ENABLE_BROKER  

public partial class WebForm1 : System.Web.UI.Page
  {
    protected void Page_Load(object sender, EventArgs e)
    {
      if (!IsPostBack)
      {
       if (Cache["Lines"] == null)
       {
         string connectionString = WebConfigurationManager.ConnectionStrings["ForTest"].ConnectionString;
         SqlConnection con = new SqlConnection(connectionString);
         string query = "SELECT dbo.Lines.Id, dbo.Lines.Value FROM dbo.Lines";
         SqlCommand cmd = new SqlCommand(query, con);
         SqlDataAdapter adapter = new SqlDataAdapter(cmd);
                  
         DataSet ds = new DataSet();
         adapter.Fill(ds, "Lines"); 
       
         SqlCacheDependency empDependency = new SqlCacheDependency(cmd);
         Cache.Insert("Lines", ds, empDependency); 
       }
      }
    }

    protected void btnResult_OnClick(object sender, EventArgs e)
    {
      var result = Cache["Lines"];
    }
}

protected void Application_Start(object sender, EventArgs e)
{
    SqlDependency.Start(WebConfigurationManager.ConnectionStrings["ForTest"].ConnectionString); 
}