DynamicFilter

 public Response Search(SearchModel search)
        {
            Dictionary<string, Expression> expressions = new Dictionary<string, Expression>
            {
                {"Price", (Expression<Func<Phone, double>>) (p => p.Price)},
                {"Brand", (Expression<Func<Phone, string>>) (p => p.Name)}
            };

            BdPhonesDbEntities db = new BdPhonesDbEntities();
            IQueryable<Phone> phones = db.Phones.Where(search.GetExpression());
            Expression<Func<Phone, double>> keySelector =  KeySelector<Func<Phone, double>>(expressions, search.OrderBy.PropertyName);            
            var result = phones.OrderBySearchModel(keySelector, false);
            var list = result.Select(p => new { p.Name, p.Brand, p.Price }).ToList();            
            return new Response(list);
        }

        private  Expression<T> KeySelector<T>(Dictionary<string, Expression> expressions, string key)
        {                        
            return (Expression<T>) expressions[key];
        }