Xander, pronounced Zander, is right in step with the current fad for names with the X-factor, whether at the start (Xander, Xen, Xavier), in the middle (Axel, Dexter, Jaxon, Huxley, Paxton, and all the Alexander and Max offspring), or at the end (Felix, Rex, Beatrix, and the three Jolie-Pitt sons' names—Maddox, Pax and Knox).
Xander, a short form of Alexander, came to the fore in the TV series Buffy the Vampire Slayer as the character Xander (born Alexander) Harris, introduced in the 1997 premiere episode and supposedly based on series creator Joss Whedon. By 1999, it had hopped onto the popularity lists, reaching its peak in 2003, though still widely used—there were more than 1300 little Xanders born last year. Twin name Zander—a General Hospital character-- has been running neck and neck with it since the Millennium. Xander Cage was Vin Diesel's name in the film xXx.
Xander Jones's middle name Dane is one of those appellations that have been more popular for a longer period of time than you might think. It has been on the Most Popular list every year since 1945, currently at Number 410, down from its high of 220 in 1986. It's one of several rhyming names now in favor—Kane/Cain, Blaine, Rain, Zane—which have taken over from the old Waynes and Duanes/Dwaynes.
Dane originated as an English surname, one of the meanings of which is "from Denmark." Its most celebrated current bearer is stand-up comic and actor Dane Cook.