.Net类与窗体做成dll(COM)在PB中使用，在dll中的代码无法直接访问xxx.exe.config，于是就进行测试....

下面是两组相关代码，注释中有详细说明

1.对个种timer组件与CacheDependency的测试

private void button10_Click(object sender, EventArgs e)        {            Console.WriteLine("当前UI线程:" +Thread.CurrentThread.IsThreadPoolThread +";" + Thread.CurrentThread.ManagedThreadId);            var file = Assembly.GetExecutingAssembly().Location + ".config";            var dep = new CacheDependency(file);            //==*****使用单个池线程************************//            //ThreadPool.QueueUserWorkItem((o) =>            //{            //    while (true)            //    {            //        if (dep.HasChanged)            //        {            //            Console.WriteLine(string.Format("是否池线程:{0};线程编号:{1}",Thread.CurrentThread.IsThreadPoolThread , Thread.CurrentThread.ManagedThreadId));            //            Console.WriteLine(string.Format("在:{0}发生更改，这里加入需要处理代码!", dep.UtcLastModified));            //            Console.WriteLine("接着开始休息3秒");            //            Thread.Sleep(3000);            //            //dep = new CacheDependency(file);            //        }            //        Thread.Sleep(100);            //    }            //});            //==*****Timers Timer 使用池线程,多线程方式 ***********//            //var t = new System.Timers.Timer();            //t.Interval = 500;            //t.Elapsed += (s,ie) => {            //        if (dep.HasChanged)            //        {            //            t.Enabled = false; //通过设置Enabled属性来控制按串行还是并行方式触发事件            //            Console.WriteLine(string.Format("是否池线程:{0};线程编号:{1}", Thread.CurrentThread.IsThreadPoolThread, Thread.CurrentThread.ManagedThreadId));            //            Console.WriteLine(string.Format("在:{0}发生更改，这里加入需要处理代码!", dep.UtcLastModified));                                 //            Console.WriteLine("接着开始休息3秒");            //            Thread.Sleep(3000);            //            t.Enabled = true;            //            //dep = new CacheDependency(file);                                    //        }                               //};            //t.Start();            //==******winform Timer 使用UI线程，单线程方式**********//            //var winfrmT = new System.Windows.Forms.Timer();            //winfrmT.Interval = 500;            //winfrmT.Tick += (s, ie) =>            //{            //        if (dep.HasChanged)            //        {            //                        //            Console.WriteLine(string.Format("是否池线程:{0};线程编号:{1}", Thread.CurrentThread.IsThreadPoolThread, Thread.CurrentThread.ManagedThreadId));            //            Console.WriteLine(string.Format("在:{0}发生更改，这里加入需要处理代码!", dep.UtcLastModified));            //            Console.WriteLine("接着开始休息3秒");            //            Thread.Sleep(3000);            //            //dep = new CacheDependency(file);            //        }            //};            //winfrmT.Start();            //==*****Threading Timer 使用池线程,多线程方式********//            var threadT = new System.Threading.Timer((o) =>            {                if (dep.HasChanged)                {                                       //==//如果当前线程被占用该timer会起用新的线程                    Console.WriteLine(string.Format("是否池线程:{0};线程编号:{1}", Thread.CurrentThread.IsThreadPoolThread, Thread.CurrentThread.ManagedThreadId));                    Console.WriteLine(string.Format("在:{0}发生更改，这里加入需要处理代码!", dep.UtcLastModified));                    Console.WriteLine("接着开始休息3秒");                    Thread.Sleep(3000);                    //dep = new CacheDependency(file);                }            },            null, 250, 500);                   }

2.采用System.Web下的缓存处理组件

public static string GetSetting(string name, string defV)        {            if (!Config.AppSettings.Settings.AllKeys.Contains(name)) return defV;            return Config.AppSettings.Settings[name].Value;        }        public static string ModelConnString        {            get            {                return Config.ConnectionStrings.ConnectionStrings["xxxEntities"].ConnectionString;            }        }        public static string ConnString        {            get            {                return Config.ConnectionStrings.ConnectionStrings["ConnString"].ConnectionString;            }        }        private static Configuration  Config        {            get            {                                var _Config = HttpRuntime.Cache["_Config"] as Configuration;                if (_Config == null )                {                    var fileMap=new ExeConfigurationFileMap();                    fileMap.ExeConfigFilename = Assembly.GetExecutingAssembly().Location + ".config";                   _Config= ConfigurationManager.OpenMappedExeConfiguration(fileMap, ConfigurationUserLevel.None);                  var fileCacheDep = new CacheDependency(fileMap.ExeConfigFilename);                  System.Web.HttpRuntime.Cache.Add("_Config", _Config, fileCacheDep, Cache.NoAbsoluteExpiration, Cache.NoSlidingExpiration, CacheItemPriority.High, null);                }                return _Config;            }                }

3.注意 System.Threading.Timer 使用局部变量时可能会被回收,其他两个貌似没问题（参考clr+via+第3版p466)