public class ClassicMovieAttribute : ValidationAttribute, IClientModelValidator
{
private int _year;

public ClassicMovieAttribute(int Year)
{
    _year = Year;
}

protected override ValidationResult IsValid(object value, ValidationContext validationContext)
{
    Movie movie = (Movie)validationContext.ObjectInstance;

    if (movie.Genre == Genre.Classic && movie.ReleaseDate.Year > _year)
    {
        return new ValidationResult(GetErrorMessage());
    }

    return ValidationResult.Success;
}