Events
Publish notifications without exposing delegate invocation.
Introduction
Events implement a type-safe publisher/subscriber relationship.
Subscribers can add and remove handlers, but only the declaring class can raise the event.
Runnable C# example
Program.cs
using System;
class Counter
{
public event EventHandler? ThresholdReached;
public void ReachThreshold() => ThresholdReached?.Invoke(this, EventArgs.Empty);
}
class Program
{
static void Main()
{
var counter = new Counter();
counter.ThresholdReached += (_, _) => Console.WriteLine("Threshold reached");
counter.ReachThreshold();
}
}
Threshold reachedPractice with the debugger
Set a breakpoint on an important assignment or condition, click Debug, and inspect the local values before stepping to the next line.
Practice with a challenge
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