public int SaveCustomer(Customer c)
 {
     try
     {
         LINQDBDataContext dc = new LINQDBDataContext();
         dc.Customers.InsertOnSubmit(c);
         dc.SubmitChanges();                        
     }
     catch (Exception)
     {
         return -1;
     }
     return 0;
 }
 partial void UpdateCustomer(Customer instance);
 partial void DeleteCustomer(Customer instance);
 partial void InsertCustomer(Customer instance);