//在项目里添加一个"全局应用程序类(Global Application Class)",在里面写这样的代码：    public class Global : System.Web.HttpApplication    {        static Timer BuildStaticPagesTimer;        static object locker = new object();        static int count;        protected void Application_Start(object sender, EventArgs e)        {            //double check lock...            if (BuildStaticPagesTimer == null)            {                lock (locker)                {                    if (BuildStaticPagesTimer == null)                    {                        //every 20 minutes, run BuildStaticPagesTimer_Callback in every 20 minutes                        BuildStaticPagesTimer = new Timer(BuildStaticPagesTimer_Callback, null, 0, 20 * 60 * 1000);                    }                }            }        }        private static void BuildStaticPagesTimer_Callback(object state)        {            Dictionary<string, string> urlsNeedToBuild = GetPagesNeedToBuiltStatic();            foreach (string oldUrl in urlsNeedToBuild.Keys)            {                string newUrl = urlsNeedToBuild[oldUrl];                Build(oldUrl, newUrl);            }        }        private static void Build(string oldUrl, string newUrl)        {            //在这里写生成静态页面的代码            throw new NotImplementedException();        }        private static Dictionary<string, string> GetPagesNeedToBuiltStatic()        {            //在这里判断哪些页面需要生成静态页面            throw new NotImplementedException();        }    }