Désérialisation d'une chaîne JSON en objet à l'aide de Newtonsoft

Question

J'ai essayé de convertir une chaîne JSON en une liste d'objets. Voici la chaîne Json.

{"fooditems":[{"item_id":1,"image_url":"http:\/\/tse1.mm.bing.net\/th?id=OIP.M201ca8470787c6ccf50f3b05118d2a27o0&pid=15.1","food_name":"Hollandia","food_description":"Maiores excepturi dolores recusandae quam. Et consequatur sunt et hic recusandae. Vero quisquam sed nemo cumque voluptates qui.","price":"144","item_special":"0","category":"2","date_created":"2016-10-18 07:12:45","date_updated":"2016-10-18 07:12:45","category_name":"Drinks"},{"item_id":2,"image_url":"http:\/\/tse1.mm.bing.net\/th?id=OIP.M201ca8470787c6ccf50f3b05118d2a27o0&pid=15.1","food_name":"Amstel Malta","food_description":"Delectus et voluptas qui. Quae dolorem rerum dignissimos et. Blanditiis porro temporibus perspiciatis voluptates similique.","price":"185","item_special":"1","category":"2","date_created":"2016-10-18 07:12:45","date_updated":"2016-10-18 07:12:45","category_name":"Drinks"},{"item_id":3,"image_url":"http:\/\/tse1.mm.bing.net\/th?id=OIP.M201ca8470787c6ccf50f3b05118d2a27o0&pid=15.1","food_name":"Egusi soup","food_description":"Aliquid et doloribus quis deserunt aut quas. Explicabo qui accusamus tempore omnis sint porro nostrum. Est nulla et commodi. Et reprehenderit rerum natus ipsa voluptas labore.","price":"152","item_special":"1","category":"1","date_created":"2016-10-18 07:12:45","date_updated":"2016-10-18 07:12:45","category_name":"Food"},{"item_id":4,"image_url":"http:\/\/tse1.mm.bing.net\/th?id=OIP.M201ca8470787c6ccf50f3b05118d2a27o0&pid=15.1","food_name":"Ponche","food_description":"Consequatur eius aut aut laudantium quis. Fuga facere a amet voluptatum. Ex optio accusamus corrupti porro repellendus ea.","price":"112","item_special":"1","category":"2","date_created":"2016-10-18 07:12:45","date_updated":"2016-10-18 07:12:45","category_name":"Drinks"},{"item_id":5,"image_url":"http:\/\/tse1.mm.bing.net\/th?id=OIP.M201ca8470787c6ccf50f3b05118d2a27o0&pid=15.1","food_name":"Teem","food_description":"Est atque eum et qui dolore ut. Dignissimos dicta qui nesciunt mollitia quo. Voluptatibus suscipit eaque laboriosam et ad. Iste illo vel consequatur doloribus.","price":"165","item_special":"1","category":"2","date_created":"2016-10-18 07:12:45","date_updated":"2016-10-18 07:12:45","category_name":"Drinks"},{"item_id":6,"image_url":"http:\/\/tse1.mm.bing.net\/th?id=OIP.M201ca8470787c6ccf50f3b05118d2a27o0&pid=15.1","food_name":"Yam Pepper soup","food_description":"Illo et ab doloribus adipisci quo hic aut. Ea fugiat ut sed minus ad non nesciunt modi. Voluptatibus nostrum labore cum maxime ullam.","price":"143","item_special":"1","category":"1","date_created":"2016-10-18 07:12:45","date_updated":"2016-10-18 07:12:45","category_name":"Food"},{"item_id":7,"image_url":"http:\/\/tse1.mm.bing.net\/th?id=OIP.M201ca8470787c6ccf50f3b05118d2a27o0&pid=15.1","food_name":"Coke","food_description":"Inventore nulla beatae incidunt delectus itaque provident accusantium. Aperiam veritatis doloribus veritatis illum rerum eum reprehenderit dolore. Ut quis fuga quia est.","price":"151","item_special":"0","category":"2","date_created":"2016-10-18 07:12:45","date_updated":"2016-10-18 07:12:45","category_name":"Drinks"},{"item_id":8,"image_url":"http:\/\/tse1.mm.bing.net\/th?id=OIP.M201ca8470787c6ccf50f3b05118d2a27o0&pid=15.1","food_name":"Jollof Rice","food_description":"Fugit labore vel ea sit voluptas consequuntur eum iste. Dolorum non distinctio sed explicabo. Saepe velit hic praesentium molestiae aperiam in autem. Soluta enim tenetur omnis tempore qui odit.","price":"172","item_special":"1","category":"1","date_created":"2016-10-18 07:12:45","date_updated":"2016-10-18 07:12:45","category_name":"Food"},{"item_id":9,"image_url":"http:\/\/tse1.mm.bing.net\/th?id=OIP.M201ca8470787c6ccf50f3b05118d2a27o0&pid=15.1","food_name":"Meat Pie","food_description":"Et vitae eveniet maxime maxime a. Explicabo consequatur quas atque non. Tempora voluptate similique dolore minus enim sit nulla eaque. Ut omnis aut incidunt assumenda excepturi.","price":"144","item_special":"0","category":"3","date_created":"2016-10-18 07:12:45","date_updated":"2016-10-18 07:12:45","category_name":"Snacks"},{"item_id":10,"image_url":"http:\/\/tse1.mm.bing.net\/th?id=OIP.M201ca8470787c6ccf50f3b05118d2a27o0&pid=15.1","food_name":"Doughnut","food_description":"Enim ipsa dolores velit autem. Illo rerum in voluptatem fugiat delectus. Sint quos provident soluta nisi ut. Cupiditate nemo temporibus qui fugiat earum fugit. Recusandae sit explicabo non exercitationem voluptatem fugiat.","price":"139","item_special":"1","category":"3","date_created":"2016-10-18 07:12:45","date_updated":"2016-10-18 07:12:45","category_name":"Snacks"},{"item_id":11,"image_url":"http:\/\/tse1.mm.bing.net\/th?id=OIP.M201ca8470787c6ccf50f3b05118d2a27o0&pid=15.1","food_name":"Fanta","food_description":"Voluptas qui asperiores qui ratione officia. Aut aliquid placeat sunt error saepe at. Repellat et ut sequi fuga aut ad debitis. Voluptatem minus sunt quam autem aut quod. Et sed dolorem qui quas.","price":"190","item_special":"1","category":"2","date_created":"2016-10-18 07:12:45","date_updated":"2016-10-18 07:12:45","category_name":"Drinks"},{"item_id":12,"image_url":"http:\/\/tse1.mm.bing.net\/th?id=OIP.M201ca8470787c6ccf50f3b05118d2a27o0&pid=15.1","food_name":"Viju Milk","food_description":"Minima excepturi voluptatem aut a sequi numquam deserunt veritatis. Enim ut vitae aut et. Non laudantium consequatur praesentium accusantium quo. Suscipit sequi dolor culpa consectetur quisquam dolorem.","price":"157","item_special":"0","category":"2","date_created":"2016-10-18 07:12:45","date_updated":"2016-10-18 07:12:45","category_name":"Drinks"},{"item_id":13,"image_url":"http:\/\/tse1.mm.bing.net\/th?id=OIP.M201ca8470787c6ccf50f3b05118d2a27o0&pid=15.1","food_name":"Nutri Milk","food_description":"Voluptatem atque consequatur aut est laudantium voluptas et. Earum et nihil minima ea ex. Et consequatur odio voluptas nihil quod.","price":"149","item_special":"1","category":"2","date_created":"2016-10-18 07:12:46","date_updated":"2016-10-18 07:12:46","category_name":"Drinks"},{"item_id":14,"image_url":"http:\/\/tse1.mm.bing.net\/th?id=OIP.M201ca8470787c6ccf50f3b05118d2a27o0&pid=15.1","food_name":"Eva Water","food_description":"Labore voluptatibus omnis omnis eaque. Occaecati aliquid voluptatum ducimus. Excepturi id magni quidem.","price":"137","item_special":"0","category":"2","date_created":"2016-10-18 07:12:46","date_updated":"2016-10-18 07:12:46","category_name":"Drinks"},{"item_id":15,"image_url":"http:\/\/tse1.mm.bing.net\/th?id=OIP.M201ca8470787c6ccf50f3b05118d2a27o0&pid=15.1","food_name":"Chapman","food_description":"Aut fugit recusandae laborum voluptas ut soluta accusantium. Impedit itaque nihil officia voluptas sed corrupti dicta. Reprehenderit id aut occaecati expedita doloribus et. Omnis quasi vel illum nam id tempora incidunt.","price":"194","item_special":"0","category":"2","date_created":"2016-10-18 07:12:46","date_updated":"2016-10-18 07:12:46","category_name":"Drinks"}]} 

Et en utilisant json2csharp je suis arrivé cette classe

public class Rootobject 
{ 
    public Fooditem[] Fooditems { get; set; } 
} 

public class Fooditem 
{ 
    public int item_id { get; set; } 
    public string image_url { get; set; } 
    public string food_name { get; set; } 
    public string food_description { get; set; } 
    public string price { get; set; } 
    public string item_special { get; set; } 
    public string category { get; set; } 
    public string date_created { get; set; } 
    public string date_updated { get; set; } 
    public string category_name { get; set; } 
} 

Mais quand désérialisation est ici l'erreur que je reçois Cannot deserialize the current JSON object (e.g. {"name":"value"}) into type 'System.Collections.Generic.List 1 [Proxy.Models.Fooditem] » parce que le type a besoin d'un tableau JSON (par exemple [ 1,2,3]) à désérialiser correctement. Pour corriger cette erreur, changez le JSON en un tableau JSON (par exemple [1,2,3]) ou changez le type désérialisé pour qu'il soit un type .NET normal (par exemple, pas un type primitif comme un entier, pas un type de collection) comme un tableau ou une liste) qui peut être désérialisé à partir d'un objet JSON. JsonObjectAttribute peut également être ajouté au type pour le forcer à désérialiser à partir d'un objet JSON. `

Voici mon code de désérialisation.

var fooditems=JsonConvert.DeserializeObject<List<Fooditem>>(json) 

Désolé, il est assez long. Apprécierait toute aide.

Answer 1

utiliser ceci pour désérialisation: var fooditems = JsonConvert.DeserializeObject<Rootobject>(jsonString);

vous essayez de jeter RootObject JSON à la liste des FoodItems est le problème

Answer 2

OK, je vois où votre problème est, Votre problème est que vous essayez pour désérialiser la chaîne json directement dans une liste, alors que le code json indique que la liste doit être une propriété dans un objet

Le code json commence par {ce qui signifie que c'est un objet qui a une liste. Donc, pour votre code pour travailler la chaîne JSON devrait commencer par [qui dit que ceci est une liste et non un objet qui a une liste

Donc, pour rendre votre code fonctionne, vous avez des options:

1. soit vous dire l'équipe de vous envoyer la chaîne JSON commençant par [

2. Utilisez cette var fooditems = JsonConvert.DeserializeObject<Rootobject>(jsonString);

dans ce c ase retournera un objet de type RootObject