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copied!<p>Sure thing. think of an event as the notification that occurs when something completes in the system that your code didn’t directly call. In C# it's really easy to get code to run when an event "fires"</p> <p>For example when a user presses a button an event will be raised or when a background network operation completes. In C# you use the += semantics to attach to the event that will be “signaled” when the event fires.</p> <p>I made you a simple C# winforms program – in it I added a button using the Visual Studio “Designer” (I just dragged a button from the Toolbox to the Window).</p> <p>You’ll see the line “button1.Click” – in this case I want to do something when the “Click” event is raised. </p> <pre><code>using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; namespace events { public partial class Form1 : Form { public Form1() { InitializeComponent(); button1.Click += new EventHandler(button1_Click); } void button1_Click(object sender, EventArgs e) { MessageBox.Show("Hi!"); } } } </code></pre> <p>You’ll also see other kinds of events in practice for example:</p> <ul> <li>Network operation has completed (<a href="http://msdn.microsoft.com/en-us/library/system.net.webclient.aspx" rel="nofollow noreferrer">WebClient.DownloadFileCompleted</a>) </li> <li>User Interfaces (resizing windows for example)</li> <li><a href="http://msdn.microsoft.com/en-us/library/system.timers.timer(VS.71).aspx" rel="nofollow noreferrer">Timers</a> (set off the timer in 10 minutes) </li> </ul>

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