Getting rid of some boiler plate code in event handling

I came across an easy way to get rid of some boiler plate code I am always writing when writing event handlers. Consider this example:

public event EventHandler SomethingHappened;

private void OnSomethingHappened() {
    var handler = SomethingHappened;
    if (handler != null) {
        handler(this, EventArgs.Empty);
    }
}

In the OnSomethingHappened() method there's a lot of unnecessary boiler plate code to make sure that we don't run into a NullReferenceException.

With a small change to the setup we can do the same with much less coding. Consider another improved example:

public event EventHandler SomethingElseHappaned = delegate { };

private void OnSomethingElseHappened() {
    SomethingElseHappened(this, EventArgs.Empty);
}

That was easy! I'm gonna do this from now on!

Happy coding!

How to check if a WaitHandle is set

Say you have a wait handle of type EventWaitHandle and want to check if it is set or not. To do this call the WaitOne(int) method with a timeout of zero. It will return true if the wait handle is set and false otherwise.

Example

using System;
using System.Threading;
 
namespace ConsoleApp {
    public class Program {
        /// <summary>
        /// Running this program will output
        ///     Wait handle is not set
        ///     Wait handle is set
        /// to the console.
        /// </summary>
        public static void Main(string[] args) {
            var waitHandle = new EventWaitHandle(false, EventResetMode.ManualReset);
 
            Console.WriteLine(waitHandle.WaitOne(0) ? "Wait handle is set" : "Wait handle is not set");
 
            waitHandle.Set();
 
            Console.WriteLine(waitHandle.WaitOne(0) ? "Wait handle is set" : "Wait handle is not set");
        }
    }
}