public ContactsDataSet Load()
 {
     ContactsDataSet data = new ContactsDataSet();
     using (ContactServiceReference.ContactServiceClient client = new ContactServiceReference.ContactServiceClient())
     {
         ContactServiceReference.Contact[] contacts = client.List();
         if (contacts != null && contacts.Length > 0)
         {
             foreach (ContactServiceReference.Contact contact in contacts)
                 data.Contacts.AddContactsRow(contact.Address, contact.DisplayName);
         }
     }
     return data;
 }
 public void Save(ContactsDataSet data)
 {
     using (ContactServiceReference.ContactServiceClient client = new ContactServiceReference.ContactServiceClient())
     {
         List<ContactServiceReference.Contact> contacts = new List<ContactServiceReference.Contact>();
         if (data != null && data.Contacts.Count > 0)
             foreach (ContactsDataSet.ContactsRow row in data.Contacts)
                 contacts.Add(new ContactServiceReference.Contact()
                 {
                     Address = row.Address,
                     DisplayName = row.DisplayName
                 });
         client.Save(contacts.ToArray<ContactServiceReference.Contact>());
     }
 }