C# event with custom arguments

EventHandler receives EventArgs as a parameter. To resolve your problem, you can build your own MyEventArgs.

 public enum MyEvents
 { 
    Event1 
 }

 public class MyEventArgs : EventArgs
 {
    public MyEvents MyEvent { get; set; }
 }

 public static event EventHandler<MyEventArgs> EventTriggered; 

 public static void Trigger(MyEvents ev) 
 { 
     if (EventTriggered != null) 
     {
         EventTriggered(null, new MyEventArgs { MyEvent = ev });
     } 
 } 

You declare a delegate for the parameters:

public enum MyEvents { Event1 }

public delegate void MyEventHandler(MyEvents e);

public static event MyEventHandler EventTriggered;

Although all events in the framework takes a parameter that is or derives from EventArgs, you can use any parameters you like. However, people are likely to expect the pattern used in the framework, which might make your code harder to follow.

I might be late in the game, but how about:

public event Action<MyEvent> EventTriggered = delegate { }; 

private void Trigger(MyEvent e) 
{ 
     EventTriggered(e);
} 

Setting the event to an anonymous delegate avoids for me to check to see if the event isn't null.

I find this comes in handy when using MVVM, like when using ICommand.CanExecute Method.