ENGLEWOOD, N.J.

WHEN your strangeness is the first thing you want people to know about yourself, as Weird Al Yankovic has advertised in his stage name for more than 30 years, you should expect strange things to happen at your concerts.

When you play here at the Bergen Performing Arts Center, as Mr. Yankovic, the accordion-wielding pop-music parodist, did on a Saturday in May, you should take it in stride when a grown-up female admirer asks you afterward to sign her pink stuffed-toy poodle, then bursts into tears when you grant her request.

When you want to end with a set of “Star Wars”-themed songs, you can expect that a battalion of local fans will join you onstage in Darth Vader and storm trooper costumes, asking for no more compensation than your handshake and a slice of pizza.

And when your computer servers crash midway through your show, just as you and your band are about to play your sendup of the treacly James Blunt love ballad “You’re Beautiful” (which you, of course, call “You’re Pitiful”), you’d better have a cover of “Radio Radio” by Elvis Costello and the Attractions ready to go in its place.