partial void DeleteContact(Contact instance);
 partial void InsertContact(Contact instance);
 partial void UpdateContact(Contact instance);
        public void UpdateCompanyName(int contactId, string companyName)
        {
            try
            {
                Contact table = new Contact();
                using (VenturadaDataContext vdc = new VenturadaDataContext())
                {
                    table = vdc.Contacts.Single(a => a.ContactId == contactId);
                    table.CompanyName = companyName;

                    vdc.SubmitChanges();
                }
            }
            catch (Exception ex)
            {

                throw ex;
            }
        }