如何每5秒调用一次方法？

Question

I have two wcf services Client.svc and Admin.svc. A method in client calls admin service method in every 5 seconds. And Admin's method which is been called by client verifies that if this method is not called within 5 seconds then update database with status "NotResponding" else update it with "IsAlive" value.

All this should be done on a separate thread.

I have written some code wherein Client uses Timer to call that method in every 5 seconds.

    public static void RegisterHeartBeat(PingRequest pingRequest)
    {
        try
        {

            string heartBeatInterval = Phoenix.API.Utility.ConfigReader.GetAppSettingsValue("HeartBeatInterval");
            int timeInSeconds = -1;

            Int32.TryParse(heartBeatInterval, out timeInSeconds);

            if (timeInSeconds != -1)
            {
                TimerCallback timerCallHeartBeat = new TimerCallback(CallRegisterHeartBeat);
                Timer timer = new Timer(timerCallHeartBeat, pingRequest, 0, (timeInSeconds * 1000)); //Multiplying by 1000, converts seconds to milliseconds
            }
            else
            {
                Exception ex = new Exception("HeartBeatInterval is not configured in web.config file");
                Phoenix.Client.API.BLL.Common.CommonUtility.CreateResultAndLogClientException(null, null, ex);
            }
        }
        catch (Exception ex)
        {
            Phoenix.Client.API.BLL.Common.CommonUtility.CreateResultAndLogClientException(null, null, ex);
        }

    }


    private static void CallRegisterHeartBeat(object state)
    {
        PhoenixClientBLL.Admin.InternalClient internalClient = new PhoenixClientBLL.Admin.InternalClient("BasicHttpBinding_IInternal");

        if (state != null)
        {
            //AdminAPI accepts Admin.PingRequest parameter which has a different format than ClientAPI PingRequest. 
            //Thus, a new object of admin ping request type is created.
            Phoenix.API.ClientServiceContracts.DataContracts.PingRequest pingRequestDC = state as Phoenix.API.ClientServiceContracts.DataContracts.PingRequest;

           //AdminAPI
            PhoenixClientBLL.Admin.PingRequest pingRequest = new PhoenixClientBLL.Admin.PingRequest();

            //Test Agent ID
            pingRequest.TestAgentId = Guid.Parse(pingRequestDC.TestAgentId);

            //Test Agent Status is not set because it will be decided in ADMIN API as per the interval difference.
            internalClient.RegisterHeartBeat(pingRequest);

        }

    }

In Admin, I check the last update date and the current date with the difference of time to update database accordingly.

    public static void RegisterHeartBeat(PingRequest pingRequest)
    {
        int status = 0;
        DateTime startTime, endTime;
        int testAgentId = -1;
        string heartBeatIntervalValue = Phoenix.API.Utility.ConfigReader.GetAppSettingsValue("HeartBeatInterval");
        int heartBeatInterval = -1;

        if(String.IsNullOrEmpty(heartBeatIntervalValue))
        {
             Common.CommonUtility.CreateResultAndLogException(null, null, new Exception("HeartBeatInterval is not configured in the configuration file"));
        }
        else
        {
                try
                {
                    string key = pingRequest.TestAgentId.ToString();
                    if (!String.IsNullOrEmpty(key))
                    {
                        if (!heartBeatTimeStamp.ContainsKey(key))
                        {
                            heartBeatTimeStamp.Add(key, System.DateTime.Now);
                        }
                        else
                        {

                            endTime = DateTime.Now;
                            if (heartBeatTimeStamp[key].HasValue)
                            {
                                startTime = heartBeatTimeStamp[key].Value;
                                var timeDiff = new TimeSpan(endTime.Ticks - startTime.Ticks);

                                //Check the configured heart beat interval value
                                Int32.TryParse(heartBeatIntervalValue, out heartBeatInterval);

                                if (heartBeatInterval != -1)
                                {
                                    if (timeDiff.Seconds > heartBeatInterval)
                                    {
                                        // add update NotResponding = 3 ..
                                        Int32.TryParse(pingRequest.TestAgentId.ToString(), out testAgentId);

                                        //If Test Agent ID is converted into integer than update table else log the error.
                                        if (testAgentId != -1)
                                        {
                                            status = DAO.TestAgentDAO.RegisterHeartBeat(testAgentId, (int)TestAgentStatus.NotResponding);
                                        }
                                        else
                                        {
                                            Common.CommonUtility.CreateResultAndLogException(null, null, new Exception("Cannot convert Test Agent ID Data type from GUID to Integer"));
                                        }

                                        //Sql Error
                                        if (0 != status)
                                        {
                                            Common.CommonUtility.CreateResultAndLogSqlError(null, status, null);

                                        }
                                    }
                                    else
                                    {
                                        // add update IsAlive= 4
                                        Int32.TryParse(pingRequest.TestAgentId.ToString(), out testAgentId);

                                        //If Test Agent ID is converted into integer than update table else log the error.
                                        if (testAgentId != -1)
                                        {
                                            status = DAO.TestAgentDAO.RegisterHeartBeat(testAgentId, (int)TestAgentStatus.IsAlive);
                                        }
                                        else
                                        {
                                            Common.CommonUtility.CreateResultAndLogException(null, null, new Exception("Cannot convert Test Agent ID Data type from GUID to Integer"));
                                        }

                                        //Sql Error
                                        if (0 != status)
                                        {
                                            Common.CommonUtility.CreateResultAndLogSqlError(null, status, null);

                                        }
                                    }
                                }
                                else
                                {
                                    Common.CommonUtility.CreateResultAndLogException(null, null, new Exception("Invalid HeartBeatInterval Value"));
                                }


                            }
                        }
                    }
                    else
                    {
                        Common.CommonUtility.CreateResultAndLogException(null, null, new Exception("Test Agent ID is incorrect or does not exists"));
                    }
                }
                catch (Exception ex)
                {
                    Common.CommonUtility.CreateResultAndLogException(null, null, ex);

                }
        }


    }

But my timer behaves in a wierd manner and never calls the admin method.. Can you please check it why? or any other logic needs to be implemented here.

Thanks Priyanka

Answer 1

You can probably use a scheduler instead of a timer. There is an open source scheduler Quartz .Net available for .NET. This can trigger your calls every 5 seconds.

Answer 2

Are you starting the Timer anywhere? Or setting Enabled to true?

http://msdn.microsoft.com/en-us/library/system.timers.timer.start.aspx

Answer 3

In your static main class instantiate a timer and create a elapsed event handler for the timer to go to when the 5 seconds are up.

in the elapsed event handler, call your method you want to run every 5 seconds. Keep in mind the timer and event handler span threads so you need to realize you could have two events happening at the same time - meaning code in a thead safe maner...

Example of timer http://msdn.microsoft.com/en-us/library/system.timers.timer(v=VS.71).aspx

i just reread your post, you are using a timer... Keep in mind THREADSAFE. if you need to stop your timer before going into the method you need called when the elapsed even ocurs.