Absolutely, cheers to that! Whenever something goes wrong and I'm feeling, let's say "less than happy", I remind myself that my emotions are a choice, and that what happened already happened so I might as well choose to be happy :-)
Sure, there are extreme situations when life throws you a curveball that won't always apply. Anger, sadness and all that other stuff is necessary sometimes, and while I'll let myself briefly indulge, I consciously decide to bring myself back to "happy" soon after.