Terms of the deals were not released Friday.
Vonleh, the ninth overall pick in this year's draft, played one season at Indiana before turning pro. The 6-foot-10 Vonleh was named Big Ten Freshman of the Year after averaging 11.3 points, nine rebounds and 1.4 blocks in 26.5 minutes per game for the Hoosiers.
Hornets coach Steve Clifford recently said he considers Vonleh "a couple of years away" from being a real contributor.
Pargo originally joined Charlotte in March, 2013, and has played in 47 games averaging 6.1 points and 1.8 assists in 11.4 minutes. Pargo is expected to be the team's No. 3 point guard behind Kemba Walker and recently signed Brian Roberts.