How can I update my UI controls from another class? : <p>I've got a form class (Form1) and another class (Calculator).</p>

<p>In Calculator I've got this method:</p>

<pre><code>public int Add(int number1, int number2)
{
    return number1 + number2;
}
</code></pre>

<p>On the form, when you click a button, the Add method should be invoked and the text of a label should be updated to the result.</p>

<p>What is the correct way of updating the label? I'm not asking for the easiest way (I know tons of them), I wanna know how this is done in big Windows Form projects.</p>

<p>I've seen lots of things how to do it (with Threads, Delegates, and the Invoke() methods, etc), but I'm not quite sure how to correctly do it myself.</p>

<p>Thanks in advance!</p>

<p>EDIT: Oh noo the downvoting :( Please help me I'm desperate</p>
