JsonConvert DeserializeObject始终为null

Question

{"product":{"title":"Test Product 0","id":29,"created_at":"2015-10-22T09:00:24Z", "price":"10:00"}}

我从web api get收到以上结果。然后我尝试将其转换为我的产品类型。但它总是给出null。

Product prod = JsonConvert.DeserializeObject<Product>(result);

public class Product
    {
        public string id { get; set; }
        public string title { get; set; }
        public string created_at { get; set; }
        public string price { get; set; }
    }