How to monitor system events using SENS class in a windows form application? Using C#

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C#

WinForms

Hi Everyone,

I need to find the total working hours of user on a system. So I need to monitor login, logoff, screen lock and screen unlock events. Then I can calculate the total working hours.

I found some code about register with COM and also SENS Interface methods.

But I don't know how to implement windows applications using c#.

Event Register Class

#region Usage of EventSystemLib

[ComImport, Guid("4E14FBA2-2E22-11D1-9964-00C04FBBB345")]
class EventSystem { }

[ComImport, Guid("7542E960-79C7-11D1-88F9-0080C7D771BF")]
class EventSubscription { }

[ComImport, Guid("AB944620-79C6-11d1-88F9-0080C7D771BF")]
class EventPublisher { }

[ComImport, Guid("cdbec9c0-7a68-11d1-88f9-0080c7d771bf")]
class EventClass { }

#endregion
class EventRegister
{
    private const string PROGID_EventSubcription = "EventSystem.EventSubription";
    static EventRegister() { }

    private static IEventSystem es = null;

    private static IEventSystem EventSystem
    {
        get {
            if (es == null)
                es = new EventSystem() as IEventSystem;
            return es;
        }
    }

    public static void SubscribeToEvents(string description, string subscriptionName, string subscriptionID, object subscriptionObject, Type subscriptionType)
    {
        //activate the subscriber
        try
        {
            //Create and populate a subscription object
            IEventSubscription sub= new EventSubscription () as IEventSubscription;
            sub.Description = description;
            sub.SubscriptionName = subscriptionName;
            sub.SubscriptionID = subscriptionID;

            //Get the GUID from the ISensLogon Interface
            sub.InterfaceID = GetInterfaceGuid(subscriptionType);
            sub.SubscriberInterface = subscriptionObject;

            //Store the actual Event
            EventSystem.Store(PROGID_EventSubcription, sub);

        }
        catch (Exception ex)
        {
            Console.WriteLine(ex);
        }
    }

    private static string GetInterfaceGuid(Type subscriptionType)
    {
        object[] attributes = subscriptionType.GetCustomAttributes(typeof(GuidAttribute), true);
        if (attributes.Length > 0)
        {
            return "{" + ((GuidAttribute)attributes[0]).Value + "}";
        }
        else
        {
            throw new NotImplementedException();
        }            
    }

    public static void UnsubscribeToEvents(string subscriberID)
    {
        try
        {
            string strCriteria = "SubscriptionID== " + subscriberID;
            int errorIndex = 0;
            EventSystem.Remove("", strCriteria, out errorIndex);
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex);
        }
    }
}

Here is my SensLogin Class

class SensLogon
    {
        public delegate void SensLogonEventHandler(string userName);
        private static SensLogonInterop eventCatcher;
        static SensLogon()
        {
        }

        #region Event Registration Code

        private static int registerCount = 0;

        private static bool IsRegistered
        {
            get
            {
                return (registerCount > 0);
            }
        }

        private static SensLogonEventHandler RegisterEvent(SensLogonEventHandler original, SensLogonEventHandler newDel)
        {
            bool ShouldRegister = (original == null);
            original = original + newDel;

            if (ShouldRegister)
            {
                if (registerCount <= 0)
                {
                    if (SensLogon.eventCatcher == null)
                    {
                        SensLogon.eventCatcher = new SensLogonInterop();
                    }
                }
                else
                {
                    //just count them
                    registerCount++;
                }
            }
            return original;
        }

        private static SensLogonEventHandler UnregisterEvent(SensLogonEventHandler original, SensLogonEventHandler oldDel)
        {
            original = original - oldDel;

            if (original == null)
            {
                registerCount--;
                if (registerCount == 0)
                {
                    //Unregister for those events
                    SensLogon.eventCatcher = null;
                }
            }

            return original;
        }

        #endregion

        #region ISensLogon Event Raising Members

        internal  static void OnDisplayLock(string bstrUserName)
        {
            if (SensLogon.displayLock != null)
            {
                SensLogon.displayLock(bstrUserName);
            }
        }

        internal  static void OnDisplayUnlock(string bstrUserName)
        {
            if(SensLogon.displayUnlock!=null)
            {
                SensLogon.displayUnlock(bstrUserName);
            }
        }

        #endregion

        #region Event Declarations

        private static SensLogonEventHandler displayLock = null;
        private static SensLogonEventHandler displayUnlock = null;

        public static event SensLogonEventHandler DisplayLock
        {
            add
            {
                SensLogon.displayLock = SensLogon.RegisterEvent(SensLogon.displayLock, value);
            }
            remove
            {
                SensLogon.displayLock = SensLogon.UnregisterEvent(SensLogon.displayLock, value);
            }
        }

        public static event SensLogonEventHandler DisplayUnlock
        {
            add
            {
                SensLogon.displayUnlock = SensLogon.RegisterEvent(SensLogon.displayUnlock, value);
            }
            remove
            {
                SensLogon.displayUnlock = SensLogon.UnregisterEvent(SensLogon.displayUnlock, value);
            }
        }

        #endregion

        #region Main Method

        static void Main(string[] args)
        {
            SensLogon.DisplayLock += new SensLogonEventHandler(SensLogon_DisplayLock);

            SensLogon.DisplayUnlock += new SensLogonEventHandler(SensLogon_DisplayUnlock);

            Console.WriteLine("Registered For SENS Events");
            Console.ReadLine();
        }

        static void SensLogon_DisplayUnlock(string userName)
        {
            Console.WriteLine("Screen Locked:" + userName);            
        }

        static void SensLogon_DisplayLock(string userName)
        {
            Console.WriteLine("Screen UnLocked:" + userName);            
        }

        #endregion

    }