¿Cómo convierto un objeto C # en una cadena JSON en .NET?

Tengo clases como estas:

class MyDate { int year, month, day; } class Lad { string firstName; string lastName; MyDate dateOfBirth; } 

Y me gustaría convertir un objeto Lad en una cadena JSON como esta:

 { "firstName":"Markoff", "lastName":"Chaney", "dateOfBirth": { "year":"1901", "month":"4", "day":"30" } } 

(sin el formateo). Encontré este enlace , pero usa un espacio de nombres que no está en .NET 4. También escuché acerca de JSON.NET , pero su sitio parece estar inactivo en este momento, y no estoy interesado en usar archivos DLL externos. ¿Hay otras opciones además de crear manualmente un escritor de cadenas JSON?

Puede usar la clase JavaScriptSerializer (agregar referencia a System.Web.Extensions ):

 using System.Web.Script.Serialization; 
 var json = new JavaScriptSerializer().Serialize(obj); 

Un ejemplo completo:

 using System; using System.Web.Script.Serialization; public class MyDate { public int year; public int month; public int day; } public class Lad { public string firstName; public string lastName; public MyDate dateOfBirth; } class Program { static void Main() { var obj = new Lad { firstName = "Markoff", lastName = "Chaney", dateOfBirth = new MyDate { year = 1901, month = 4, day = 30 } }; var json = new JavaScriptSerializer().Serialize(obj); Console.WriteLine(json); } } 

Como a todos nos encantan los liners

… este depende del paquete Newtonsoft NuGet, que es popular y mejor que el serializador predeterminado.

 Newtonsoft.Json.JsonConvert.SerializeObject(new {foo = "bar"}) 

Documentación: Serialización y deserialización de JSON

Use la clase DataContractJsonSerializer : MSDN1 , MSDN2 .

Mi ejemplo: AQUÍ .

También puede deserializar de forma segura objetos a partir de una cadena JSON, a diferencia de JavaScriptSerializer . Pero personalmente todavía prefiero Json.NET .

Use la biblioteca Json.Net , puede descargarla desde Nuget Packet Manager.

Serializando a Json String:

  var obj = new Lad { firstName = "Markoff", lastName = "Chaney", dateOfBirth = new MyDate { year = 1901, month = 4, day = 30 } }; var jsonString = Newtonsoft.Json.JsonConvert.SerializeObject(obj); 

Deserializando al objeto:

 var obj = Newtonsoft.Json.JsonConvert.DeserializeObject(jsonString ); 

Wooou! Realmente mejor usando un marco JSON 🙂

Aquí está mi ejemplo usando Json.NET ( http://james.newtonking.com/json ):

 using System; using System.Collections.Generic; using System.Text; using Newtonsoft.Json; using System.IO; namespace com.blogspot.jeanjmichel.jsontest.model { public class Contact { private Int64 id; private String name; List
addresses; public Int64 Id { set { this.id = value; } get { return this.id; } } public String Name { set { this.name = value; } get { return this.name; } } public List
Addresses { set { this.addresses = value; } get { return this.addresses; } } public String ToJSONRepresentation() { StringBuilder sb = new StringBuilder(); JsonWriter jw = new JsonTextWriter(new StringWriter(sb)); jw.Formatting = Formatting.Indented; jw.WriteStartObject(); jw.WritePropertyName("id"); jw.WriteValue(this.Id); jw.WritePropertyName("name"); jw.WriteValue(this.Name); jw.WritePropertyName("addresses"); jw.WriteStartArray(); int i; i = 0; for (i = 0; i < addresses.Count; i++) { jw.WriteStartObject(); jw.WritePropertyName("id"); jw.WriteValue(addresses[i].Id); jw.WritePropertyName("streetAddress"); jw.WriteValue(addresses[i].StreetAddress); jw.WritePropertyName("complement"); jw.WriteValue(addresses[i].Complement); jw.WritePropertyName("city"); jw.WriteValue(addresses[i].City); jw.WritePropertyName("province"); jw.WriteValue(addresses[i].Province); jw.WritePropertyName("country"); jw.WriteValue(addresses[i].Country); jw.WritePropertyName("postalCode"); jw.WriteValue(addresses[i].PostalCode); jw.WriteEndObject(); } jw.WriteEndArray(); jw.WriteEndObject(); return sb.ToString(); } public Contact() { } public Contact(Int64 id, String personName, List
addresses) { this.id = id; this.name = personName; this.addresses = addresses; } public Contact(String JSONRepresentation) { //To do } } }

La prueba:

 using System; using System.Collections.Generic; using com.blogspot.jeanjmichel.jsontest.model; namespace com.blogspot.jeanjmichel.jsontest.main { public class Program { static void Main(string[] args) { List
addresses = new List
(); addresses.Add(new Address(1, "Rua Dr. Fernandes Coelho, 85", "15º andar", "São Paulo", "São Paulo", "Brazil", "05423040")); addresses.Add(new Address(2, "Avenida Senador Teotônio Vilela, 241", null, "São Paulo", "São Paulo", "Brazil", null)); Contact contact = new Contact(1, "Ayrton Senna", addresses); Console.WriteLine(contact.ToJSONRepresentation()); Console.ReadKey(); } } }

El resultado:

 { "id": 1, "name": "Ayrton Senna", "addresses": [ { "id": 1, "streetAddress": "Rua Dr. Fernandes Coelho, 85", "complement": "15º andar", "city": "São Paulo", "province": "São Paulo", "country": "Brazil", "postalCode": "05423040" }, { "id": 2, "streetAddress": "Avenida Senador Teotônio Vilela, 241", "complement": null, "city": "São Paulo", "province": "São Paulo", "country": "Brazil", "postalCode": null } ] } 

Ahora implementaré el método constructor que recibirá una cadena JSON y rellenará los campos de la clase.

Si estás en un controlador web ASP.NET MVC es tan simple como:

 string ladAsJson = Json(Lad); 

No puedo creer que nadie haya mencionado esto.

Si no son muy grandes, probablemente sea su caso exportarlo como Json. También esto hace portátil entre todas las plataformas

  using Newtonsoft.Json; [TestMethod] public void ExportJson() { double[,] b = new double[,] { { 110, 120, 130, 140, 150 }, { 1110, 1120, 1130, 1140, 1150 }, { 1000, 1, 5 ,9, 1000}, {1110, 2, 6 ,10,1110}, {1220, 3, 7 ,11,1220}, {1330, 4, 8 ,12,1330} }; string jsonStr = JsonConvert.SerializeObject(b); Console.WriteLine(jsonStr); string path = "X:\\Programming\\workspaceEclipse\\PyTutorials\\src\\tensorflow_tutorials\\export.txt"; File.WriteAllText(path, jsonStr); } 

Yo votaría por el Serializador JSON de ServiceStack:

 using ServiceStack.Text string jsonString = new { FirstName = "James" }.ToJson(); 

También es el serializador JSON más rápido disponible para .NET: http://www.servicestack.net/benchmarks/

Use el siguiente código para convertir XML a JSON.

 var json = new JavaScriptSerializer().Serialize(obj); 

Tan fácil como esto, también funciona para objetos dynamics (tipo objeto):

 string json = new System.Web.Script.Serialization.JavaScriptSerializer().Serialize(MYOBJECT); 

Utilice estas herramientas para generar clases C #, luego use este código para serializar su objeto

  var json = new JavaScriptSerializer().Serialize(obj); 

Serializador

  public static void WriteToJsonFile(string filePath, T objectToWrite, bool append = false) where T : new() { var contentsToWriteToFile = JsonConvert.SerializeObject(objectToWrite, new JsonSerializerSettings { Formatting = Formatting.Indented, }); using (var writer = new StreamWriter(filePath, append)) { writer.Write(contentsToWriteToFile); } } 

Objeto

 namespace MyConfig { public class AppConfigurationSettings { public AppConfigurationSettings() { /* initialize the object if you want to output a new document * for use as a template or default settings possibly when * an app is started. */ if (AppSettings == null) { AppSettings=new AppSettings();} } public AppSettings AppSettings { get; set; } } public class AppSettings { public bool DebugMode { get; set; } = false; } } 

Implementación

 var jsonObject = new AppConfigurationSettings(); WriteToJsonFile(file.FullName, jsonObject); 

Salida

 { "AppSettings": { "DebugMode": false } } 

Hay una utilidad realmente ingeniosa aquí: http://csharp2json.io/

Tenga cuidado de crear su clase con el atributo correcto también:

Cree esta clase con el atributo como muestra el ejemplo C # seguido de vb.net exmpale

DO#

 using Microsoft.VisualBasic; using System; using System.Collections; using System.Collections.Generic; using System.Data; using System.Diagnostics; using System.Web; using System.Web.Script.Serialization; namespace Samples { [Serializable()] public class Customer { private int _idcustomer; public int IDCustomer { get { return _idcustomer; } set { _idcustomer = value; } } private System.DateTime _RegistrationDate; public System.DateTime RegistrationDate { get { return _RegistrationDate; } set { _RegistrationDate = value; } } private string _Name; public string Name { get { return _Name; } set { _Name = value; } } private string _Surname; public string Surname { get { return _Surname; } set { _Surname = value; } } } [Serializable()] public class Product { private int _ProductID; public int ProductID { get { return _ProductID; } set { _ProductID = value; } } private string _ProductName; public string ProductName { get { return _ProductName; } set { _ProductName = value; } } private int _Price; public int Price { get { return _Price; } set { _Price = value; } } private bool _inStock; public bool inStock { get { return _inStock; } set { _inStock = value; } } } [Serializable()] public class Order { private int _OrderId; public int OrderID { get { return _OrderId; } set { _OrderId = value; } } private int _customerID; public int CustomerID { get { return _customerID; } set { _customerID = value; } } private List _ProductsList; public List ProductsList { get { return _ProductsList; } set { _ProductsList = value; } } private System.DateTime _PurchaseDate; public System.DateTime PurchaseDate { get { return _PurchaseDate; } set { _PurchaseDate = value; } } private string _PaymentMethod; public string PaymentMethod { get { return _PaymentMethod; } set { _PaymentMethod = value; } } public string ToJson() { string json = string.Empty; JavaScriptSerializer js = new JavaScriptSerializer(); json = js.Serialize(this); js = null; return json; } } } 

EJEMPLO DE VBNET

 Imports System Imports System.Web Imports System.Web.Script.Serialization Namespace Samples  Public Class Customer Private _idcustomer As Integer Public Property IDCustomer() As Integer Get Return _idcustomer End Get Set(ByVal value As Integer) _idcustomer = value End Set End Property Private _RegistrationDate As Date Public Property RegistrationDate() As Date Get Return _RegistrationDate End Get Set(ByVal value As Date) _RegistrationDate = value End Set End Property Private _Name As String Public Property Name() As String Get Return _Name End Get Set(ByVal value As String) _Name = value End Set End Property Private _Surname As String Public Property Surname() As String Get Return _Surname End Get Set(ByVal value As String) _Surname = value End Set End Property End Class  Public Class Product Private _ProductID As Integer Public Property ProductID() As Integer Get Return _ProductID End Get Set(ByVal value As Integer) _ProductID = value End Set End Property Private _ProductName As String Public Property ProductName() As String Get Return _ProductName End Get Set(ByVal value As String) _ProductName = value End Set End Property Private _Price As Integer Public Property Price() As Integer Get Return _Price End Get Set(ByVal value As Integer) _Price = value End Set End Property Private _inStock As Boolean Public Property inStock() As Boolean Get Return _inStock End Get Set(ByVal value As Boolean) _inStock = value End Set End Property End Class  Public Class Order Private _OrderId As Integer Public Property OrderID() As Integer Get Return _OrderId End Get Set(ByVal value As Integer) _OrderId = value End Set End Property Private _customerID As Integer Public Property CustomerID() As Integer Get Return _customerID End Get Set(ByVal value As Integer) _customerID = value End Set End Property Private _ProductsList As List(Of Product) Public Property ProductsList() As List(Of Product) Get Return _ProductsList End Get Set(ByVal value As List(Of Product)) _ProductsList = value End Set End Property Private _PurchaseDate As Date Public Property PurchaseDate() As Date Get Return _PurchaseDate End Get Set(ByVal value As Date) _PurchaseDate = value End Set End Property Private _PaymentMethod As String Public Property PaymentMethod() As String Get Return _PaymentMethod End Get Set(ByVal value As String) _PaymentMethod = value End Set End Property Public Function ToJson() As String Dim json As String = String.Empty Dim js As New JavaScriptSerializer json = js.Serialize(Me) js = Nothing Return json End Function End Class 

Espacio de nombres final

El segundo paso es crear una prueba simple de datos como esta:

DO#

  void Main() { List ListProducts = new List(); ListProducts.Add(new Samples.Product(), With, {.inStock=False,.Price=10, .ProductID=1,.ProductName=BookOne); ListProducts.Add(new Samples.Product(), With, {.inStock=False,. Price=10, .ProductID=2, .ProductName=Hotels California); ListProducts.Add(new Samples.Product(), With, {.inStock=False,.Price=10,.ProductID=3,.ProductName=Cbr); ListProducts.Add(new Samples.Product(), With, {.inStock=False,.Price=10,.ProductID=4,.ProductName=Mustang); ListProducts.Add(new Samples.Product(), With, {.inStock=False,.Price=10, .ProductID=15,.ProductName=Anything); ListProducts.Add(new Samples.Product(), With, {.inStock=False,.Price=10,.ProductID=38,.ProductName=Monster Truck); Samples.Customer Customer = new Samples.Customer(); // With... Customer.IDCustomer = 1; Customer.Name = "Customer1"; Customer.RegistrationDate = Now; Customer.Surname = "SurnameCustomer"; Samples.Order Order = new Samples.Order(); // With... Order.CustomerID = Customer.IDCustomer; Order.OrderID = 1; Order.PaymentMethod = "PayPal"; Order.ProductsList = ListProducts; Order.PurchaseDate = Now; Console.WriteLine(Order.ToJson); Console.ReadLine(); } 

VB.NET

 Sub Main() Dim ListProducts As New List(Of Samples.Product) ListProducts.Add(New Samples.Product With {.inStock = False, .Price = 10, .ProductID = 1, .ProductName = "BookOne"}) ListProducts.Add(New Samples.Product With {.inStock = False, .Price = 10, .ProductID = 2, .ProductName = "Hotels California"}) ListProducts.Add(New Samples.Product With {.inStock = False, .Price = 10, .ProductID = 3, .ProductName = "Cbr"}) ListProducts.Add(New Samples.Product With {.inStock = False, .Price = 10, .ProductID = 4, .ProductName = "Mustang"}) ListProducts.Add(New Samples.Product With {.inStock = False, .Price = 10, .ProductID = 15, .ProductName = "Anything"}) ListProducts.Add(New Samples.Product With {.inStock = False, .Price = 10, .ProductID = 38, .ProductName = "Monster Truck"}) Dim Customer As New Samples.Customer With {.IDCustomer = 1, .Name = "Customer1",.RegistrationDate = Now, .Surname ="SurnameCustomer"} Dim Order As New Samples.Order With { .CustomerID = Customer.IDCustomer, .OrderID = 1, .PaymentMethod = "PayPal", .ProductsList = ListProducts, .PurchaseDate = Now } Console.WriteLine(Order.ToJson) Console.ReadLine() End Sub 

Y este es el resultado final:

 {"OrderID":1,"CustomerID":1,"ProductsList":[{"ProductID":1,"ProductName":"BookOn e","Price":10,"inStock":false},{"ProductID":2,"ProductName":"Hotels California", "Price":10,"inStock":false},{"ProductID":3,"ProductName":"Cbr","Price":10,"inSto ck":false},{"ProductID":4,"ProductName":"Mustang","Price":10,"inStock":false},{" ProductID":15,"ProductName":"Anything","Price":10,"inStock":false},{"ProductID": 38,"ProductName":"Monster Truck","Price":10,"inStock":false}],"PurchaseDate":"\/ Date(1396642206155)\/","PaymentMethod":"PayPal"} 

Recuerde agregar una referencia a system.web.extension.dll para lograr su objective.