Answers for "c# event keyword"

event keyword C#

//EN
The event keyword is used to declare an event in a publisher class.
//FR
Le mot clé event sert à déclarer un événement dans une classe d’éditeur.

public event System.Action myEvent;
myEvent?.Invoke();

public event System.Action<T> myEventWithType;
myEventWithType?.invoke(T);

C# events

//1. (Optionally) Make a event class to return data in. Microsoft has a EventArgs class you can derive from, but benifits are minimal besides ahereance to standards.
//2. Make a event class 2 sub scribe to or that will publish the event.
//3. In any place you wish to use the event (subscribe to the event) or subscribe to the event.
    /// 1. An event argument to handle the Data received
    public class YourEventReceiveEventArgs : EventArgs
    {
    	//give out any properties you wish the subscriber to have here.
		//often makeing the set private so the event can be secure is a good idea.
        public byte[] YourDataAsProperties { get; private set; }
        public DateTime DateTime { get; private set; } = DateTime.UtcNow;
        internal DataReceiveEventArgs(byte[] Data){ this.Data = Data; }
    }
	//2. In the Class that will be raise (creates and orignates from) the event add a delegate EventHandler
	public class YourEventPublishingClass
    {
      	//Create a delegate of the signiture of methods you would like to subscribe the event to
      	//Optionally: The object is sender is optional but is a ahereance to standards.
      	//Optionally: Add the event class that you would like to pass data in
		public delegate void YourEventHandler(object Sender, DataReceiveEventArgs e);
		//create Your event using your newly created signature.
    	public event YourEventHandler YourEvent;
      	//Create a way to raise your event this could be a call to check
      	//something durring another in anthor thread or async watch method.
		protected void RaseEvent()
        {
          //if(Condtions are met)
          if(true)
          	handler?.Invoke(this, e);
        }
    }
	//3. Subscribe to event and attach a method to rase on the event
	private class YourSubscriberClass
	{
		//using instance of the class (or you could have a static style class in some rare cases) subscribe
      	//note how you instance and pass the class is up to you.
		private YourEventPublishingClass YourEventPublishingClassProperty;
      	public YourSubscriberClass(YourEventPublishingClass EventClassIn)
        {
      	   YourEventPublishingClassProperty = EventClassIn;
           YourEventPublishingClassProperty.YourEvent += YourEventRecivedMethodEvent;
        }
		//Make sure you your event follows the signature of your delagate
    	private void YourEventRecivedMethodEvent(object Sender, YourEventReceiveEventArgs e)
    	{
      		//replace this with your code
    	}
	}

c# event

class Counter
{
    public event EventHandler ThresholdReached;

    protected virtual void OnThresholdReached(EventArgs e)
    {
        EventHandler handler = ThresholdReached;
        handler?.Invoke(this, e);
    }

    // provide remaining implementation for the class
}