asp.net – SqlCacheDependency不起作用

ALTER DATABASE ForTest SET ENABLE_BROKER

在managmeng工作室.

Aspx页面：

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"];
    }
}

我运行此页面并向Cache添加行,然后在管理工作室中添加行,当我点击按钮时,我期待
缓存将被更改但缓存仍然是旧的.
我找不到我做错了什么:(你能给我一些提示,我怎么能解决这个问题？

谢谢

更新：
我伪造说在global.aspx我运行：

SqlDependency.Start(
    WebConfigurationManager.ConnectionStrings["ForTest"].ConnectionString
);