//================================================================================ private void validateVesselInCompanyExistance(DomainObjects.VesselInCompany vesselInCompany, Company introducer, ICompanyDomainService companyDomainService) { var vessels = companyDomainService.GetCompanyVessels(introducer.Id); if (vessels.Count(v => v.Id == vesselInCompany.Id) != 1) throw new BusinessRuleException("", "The vessel is not assigned to company."); }