Hardison was born in Bedford–Stuyvesant, Brooklyn, New York, the son of Bethann (née Hardison), a fashion model who owned a modeling agency, and Donald McFadden, an art collector.
Hardison was formerly married to singer Chanté Moore; they have a daughter named Sophia.
Hardison remains a close friend of actor Darryl Bell, who played his best friend Ron Johnson on A Different World; he makes an appearance alongside Bell on FOX's Househusbands of Hollywood.
Hardison was a starring cast member on the sitcom A Different World as Dwayne Wayne, and a regular cast member of K.C. Undercover and the short-lived sitcoms Abby and Between Brothers. His career was managed predominantly by his mother, Bethann Hardison. He has also guest starred on several other sitcoms, including Living Single, Girlfriends, Under One Roof, The Boondocks (as himself), Greek, Parenthood, and on Everybody Hates Chris as the judge. His movies include School Daze, Def by Temptation, Vampire in Brooklyn, 30 Years to Life, Made of Honor, Escapee, The 6th Man, Drive, Renaissance Man, Panther, The Fantasia Barrino Story: Life Is Not a Fairy Tale, Bratz, Biker Boyz, Who's Your Daddy?, The Crow: Stairway to Heaven, I'm Gonna Git You Sucka, Blind Faith, Showtime and White Men Can't Jump. He also appears as an actor in the 2013 PlayStation 3 exclusive video game Beyond: Two Souls as Cole Freeman.
- He was reunited on the series with former co-star Jasmine Guy playing Erica King.
- Episodes of K.C. Undercover he has directed:
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