In New York, a conditional discharge is a sentence of confinement if the defendant fails to perform the conditions of probation within a certain period of time. Once the time period elapses, so long as the conditions are satisfied, the case is sealed. However, this is not the same as the charges being dismissed. If one pleads guilty to a misdemeanor or felony, it would be a criminal conviction. On the other hand, if the crime was a violation, then regardless of whether a conditional discharge was imposed, this would not qualify as a criminal conviction.
Also keep in mind, while the case is sealed, this does not include the court file. Certain individuals will still have access to the court file regardless of whether the case is sealed.