ASP.NET HTTP客户端JSON响应

Question

Asp.net c#. This is my json string that i am getting from external web address, i want to store it in a list and then display it using gridview. it is giving an error ie.

Cannot deserialize the current JSON object (eg {"name":"value"}) into type 'System.Collections.Generic.List`1[AMS_WEB_Form.Employee]' because the type requires a JSON array (eg [1,2,3]) to deserialize correctly.

To fix this error either change the JSON to a JSON array (eg [1,2,3]) or change the deserialized type so that it is a normal .NET type (eg not a primitive type like integer, not a collection type like an array or List) that can be deserialized from a JSON object. JsonObjectAttribute can also be added to the type to force it to deserialize from a JSON object.

Path 'employees', line 1, position 13.

plz help,

class that i am using,..

public class Employee
{
    public int employee_id { get; set; }
    public string employee_name { get; set; }
}


public class RootObject
{
    public List<Employee> employees { get; set; }
}

This is what i am doing....and calling this task in PageLoads event of view.

async Task RunAsyncGetDataFromSource()
{
  using( var client = new HttpClient() )
  {               
     //HTTP get
     HttpResponseMessage response = await client.GetAsync("http://192.168.88.598:6598/employees");
     response.EnsureSuccessStatusCode();

     if( response.IsSuccessStatusCode )
     {
       var jsonString =  response.Content.ReadAsStringAsync().Result;
       var data = JsonConvert.DeserializeObject<List<Employee>>(jsonString);

       GridExternalUsersData.DataSource = data;
       GridExternalUsersData.DataBind();

       Response.Write("<script>alert('Data loaded successfully');</script>");
    }
  }           
}

My JSON Output from WebAPI is in this format.

"{\\"employees\\":[{\\"employee_id\\":1,\\"employee_name\\":\\"Dalton Schimmel\\"},{\\"employee_id\\":2,\\"employee_name\\":\\"Caitlyn O'Kon\\"},{\\"employee_id\\":3,\\"employee_name\\":\\"Timmothy Bartell\\"},{\\"employee_id\\":4,\\"employee_name\\":\\"Mauricio Lind\\"},{\\"employee_id\\":5,\\"employee_name\\":\\"Mr. Imani Pfannerstill\\"},{\\"employee_id\\":6,\\"employee_name\\":\\"Mrs. Reagan Wehner\\"},{\\"employee_id\\":7,\\"employee_name\\":\\"Citlalli McCullough II\\"},{\\"employee_id\\":8,\\"employee_name\\":\\"Mrs. Fabian Leffler\\"},{\\"employee_id\\":9,\\"employee_name\\":\\"Blanca Langosh\\"},{\\"employee_id\\":10,\\"employee_name\\":\\"Kennith Watsica\\"},{\\"employee_id\\":11,\\"employee_name\\":\\"Fermin Leannon\\"},{\\"employee_id\\":12,\\"employee_name\\":\\"Estelle Windler\\"},{\\"employee_id\\":13,\\"employee_name\\":\\"Kurt Skiles\\"},{\\"employee_id\\":14,\\"employee_name\\":\\"Sienna Medhurst\\"},{\\"employee_id\\":15,\\"employee_name\\":\\"Orlando Bednar DVM\\"},{\\"employee_id\\":16,\\"employee_name\\":\\"Harley Leffler\\"},{\\"employee_id\\":17,\\"employee_name\\":\\"Nathaniel Crooks\\"},{\\"employee_id\\":18,\\"employee_name\\":\\"Hortense Jerde IV\\"},{\\"employee_id\\":19,\\"employee_name\\":\\"Coty Mills\\"},{\\"employee_id\\":20,\\"employee_name\\":\\"Savannah Grimes\\"},{\\"employee_id\\":21,\\"employee_name\\":\\"Ms. Darrick Moore\\"},{\\"employee_id\\":22,\\"employee_name\\":\\"Meta Hermann MD\\"},{\\"employee_id\\":23,\\"employee_name\\":\\"Mr. Ellsworth Sauer\\"},{\\"employee_id\\":24,\\"employee_name\\":\\"Salvatore Marks\\"},{\\"employee_id\\":25,\\"employee_name\\":\\"Rory Bahringer I\\"},{\\"employee_id\\":26,\\"employee_name\\":\\"Rory Robel Sr.\\"},{\\"employee_id\\":27,\\"employee_name\\":\\"Katheryn Erdman\\"},{\\"employee_id\\":28,\\"employee_name\\":\\"Lexie Deckow Jr.\\"},{\\"employee_id\\":29,\\"employee_name\\":\\"Erling Jenkins\\"},{\\"employee_id\\":30,\\"employee_name\\":\\"Chris Gusikowski\\"},{\\"employee_id\\":31,\\"employee_name\\":\\"Kelli Mraz\\"},{\\"employee_id\\":32,\\"employee_name\\":\\"Gregg Hartmann\\"},{\\"employee_id\\":33,\\"employee_name\\":\\"Darrel Olson\\"},{\\"employee_id\\":34,\\"employee_name\\":\\"Roxane Nicolas\\"},{\\"employee_id\\":35,\\"employee_name\\":\\"Julian Hintz\\"},{\\"employee_id\\":36,\\"employee_name\\":\\"Elian White\\"},{\\"employee_id\\":37,\\"employee_name\\":\\"Annabel Nader\\"},{\\"employee_id\\":38,\\"employee_name\\":\\"Brycen Vandervort V\\"},{\\"employee_id\\":39,\\"employee_name\\":\\"Ms. Gerald Roob\\"},{\\"employee_id\\":40,\\"employee_name\\":\\"Dr. Lesley Feil\\"},{\\"employee_id\\":41,\\"employee_name\\":\\"Owen Schmidt\\"},{\\"employee_id\\":42,\\"employee_name\\":\\"Kayden Effertz\\"},{\\"employee_id\\":43,\\"employee_name\\":\\"Muhammad Funk\\"},{\\"employee_id\\":44,\\"employee_name\\":\\"Justyn Klein\\"},{\\"employee_id\\":45,\\"employee_name\\":\\"Ms. Jennie Pfannerstill\\"},{\\"employee_id\\":46,\\"employee_name\\":\\"Ms. Celestine Konopelski\\"},{\\"employee_id\\":47,\\"employee_name\\":\\"Kayden Jones\\"},{\\"employee_id\\":48,\\"employee_name\\":\\"Dr. Anabelle Emmerich\\"},{\\"employee_id\\":49,\\"employee_name\\":\\"Mrs. Isabell Kemmer\\"},{\\"employee_id\\":50,\\"employee_name\\":\\"Jovani Kiehn\\"},{\\"employee_id\\":51,\\"employee_name\\":\\"Otis Schiller\\"},{\\"employee_id\\":52,\\"employee_name\\":\\"Mrs. Aron Daniel\\"},{\\"employee_id\\":53,\\"employee_name\\":\\"Lurline Mayer\\"},{\\"employee_id\\":54,\\"employee_name\\":\\"Tiana Wisozk\\"},{\\"employee_id\\":55,\\"employee_name\\":\\"Laila Predovic\\"},{\\"employee_id\\":56,\\"employee_name\\":\\"Moises Carter\\"},{\\"employee_id\\":57,\\"employee_name\\":\\"Lizzie Yost\\"},{\\"employee_id\\":58,\\"employee_name\\":\\"Zoe Kirlin\\"},{\\"employee_id\\":59,\\"employee_name\\":\\"Kirk Romaguera\\"},{\\"employee_id\\":60,\\"employee_name\\":\\"Travis Orn\\"},{\\"employee_id\\":61,\\"employee_name\\":\\"Dr. Okey Mertz\\"},{\\"employee_id\\":62,\\"employee_name\\":\\"Kristoffer Gerhold\\"},{\\"employee_id\\":63,\\"employee_name\\":\\"Unique Beier\\"},{\\"employee_id\\":64,\\"employee_name\\":\\"Mrs. Halle Runolfsson\\"},{\\"employee_id\\":65,\\"employee_name\\":\\"Ariane Kris\\"},{\\"employee_id\\":66,\\"employee_name\\":\\"Irma Witting III\\"},{\\"employee_id\\":67,\\"employee_name\\":\\"Rupert Streich PhD\\"},{\\"employee_id\\":68,\\"employee_name\\":\\"Dahlia Kemmer Sr.\\"},{\\"employee_id\\":69,\\"employee_name\\":\\"Ms. George Thompson\\"},{\\"employee_id\\":70,\\"employee_name\\":\\"Emie Green IV\\"},{\\"employee_id\\":71,\\"employee_name\\":\\"Miss Ibrahim Botsford\\"},{\\"employee_id\\":72,\\"employee_name\\":\\"Felton Waters IV\\"},{\\"employee_id\\":73,\\"employee_name\\":\\"Letitia Thiel\\"},{\\"employee_id\\":74,\\"employee_name\\":\\"Marquis Corwin\\"},{\\"employee_id\\":75,\\"employee_name\\":\\"Destini Rogahn V\\"},{\\"employee_id\\":76,\\"employee_name\\":\\"Carleton Steuber\\"},{\\"employee_id\\":77,\\"employee_name\\":\\"Amiya Von PhD\\"},{\\"employee_id\\":78,\\"employee_name\\":\\"Adele Kunde\\"},{\\"employee_id\\":79,\\"employee_name\\":\\"Miss Elijah Glover\\"},{\\"employee_id\\":80,\\"employee_name\\":\\"Joelle Thiel\\"},{\\"employee_id\\":81,\\"employee_name\\":\\"Eino Bogan\\"},{\\"employee_id\\":82,\\"employee_name\\":\\"Ms. Jake Kerluke\\"},{\\"employee_id\\":83,\\"employee_name\\":\\"Ethyl Waters\\"},{\\"employee_id\\":84,\\"employee_name\\":\\"Vanessa Lindgren\\"},{\\"employee_id\\":85,\\"employee_name\\":\\"Valentin Cummerata\\"},{\\"employee_id\\":86,\\"employee_name\\":\\"Dr. Halle Fadel\\"},{\\"employee_id\\":87,\\"employee_name\\":\\"Savanah King\\"},{\\"employee_id\\":88,\\"employee_name\\":\\"Christop Effertz\\"},{\\"employee_id\\":89,\\"employee_name\\":\\"Cristopher Jacobs\\"},{\\"employee_id\\":90,\\"employee_name\\":\\"Prudence Cruickshank II\\"},{\\"employee_id\\":91,\\"employee_name\\":\\"Karlee Herman\\"},{\\"employee_id\\":92,\\"employee_name\\":\\"Rosamond Rau\\"},{\\"employee_id\\":93,\\"employee_name\\":\\"Marina Fritsch\\"},{\\"employee_id\\":94,\\"employee_name\\":\\"Stefanie Johns\\"},{\\"employee_id\\":95,\\"employee_name\\":\\"Tevin Murazik\\"},{\\"employee_id\\":96,\\"employee_name\\":\\"Audra Bins\\"},{\\"employee_id\\":97,\\"employee_name\\":\\"Melba Larson\\"},{\\"employee_id\\":98,\\"employee_name\\":\\"Asa Schaefer\\"},{\\"employee_id\\":99,\\"employee_name\\":\\"Spencer Jenkins II\\"},{\\"employee_id\\":100,\\"employee_name\\":\\"Elda Brakus\\"}]}" string

Answer 1

You will need to change your JsonConvert to :
var data = JsonConvert.DeserializeObject<RootObject>(jsonString);

Alternatively you could remove the employees section from your JSON