public IEnumerable <ValidationResult> Validate(ValidationContext validationContext) { var results = new List <ValidationResult>(); if (GroupId.IsNot24BitHex()) { results.Add(new ValidationResult($"{nameof(GroupId)} must be a valid 24-bit hex string.", new[] { nameof(GroupId) })); } if (RegionId.IsNot24BitHex()) { results.Add(new ValidationResult($"{nameof(RegionId)} must be a valid 24-bit hex string.", new[] { nameof(RegionId) })); } return(results); }