What's that about? You give incomplete information and ask for advice, an experienced home handyman (me) tries to come to your assistance and fill in the gaps with some educated guesswork, then you reveal that you're in an apartment and there's a concrete wall behind the dryer that you can't fasten things to (actually you can, and you can also invisibly repair it when you leave so the landlord will never know, if you know how), and you respond as if I were being tiresome and making it overly complicated. *sigh* women. Sheesh. This is not as simple a problem as you thought.
But 'cause I'm such a nice guy, I'll tell you a few other things. First, you're unlikely to find something that'll fit perfectly over your dryer, that's not what those units are designed for. And second, be sure that the braces on the legs, like what you see in that image you posted, don't interfere with the dryer's venting or power cord. Odds are the dryer's vent pipe will be on the back or side of the unit just about where those bottom braces are. Take a measured drawing of the dryer with you on your shopping trip, with those things marked on it. And take a tape measure too, so you can check measurements on whatever you find. And third, also note where the dryer plugs into the wall and where the vent pipe exits your apartment, to be sure the shelving unit won't interfere with access to those either.
