如何在.NET中将C＃对象转换为JSON字符串？

How do I turn a C# object into a JSON string in .NET?

我有这样的课程：

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class MyDate
{
int year, month, day;
}

class Lad
{
string firstName;
string lastName;
MyDate dateOfBirth;
}

我想把一个Lad对象转换成这样的JSON字符串：

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

(不带格式)。我找到了这个链接，但它使用的名称空间不在.NET 4中。我也听说过json.net，但他们的网站目前似乎已经关闭了，我不喜欢使用外部的dll文件。除了手动创建JSON字符串编写器之外，还有其他选项吗？

相关讨论

既然我们都喜欢一句话

…这一个依赖于newtonsoft nuget包，这是流行的，比默认的序列化程序更好。

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

文档：序列化和反序列化JSON

相关讨论

您可以使用JavaScriptSerializer类(添加对System.Web.Extensions的引用)：

1	using System.Web.Script.Serialization;

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

一个完整的例子：

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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);
}
}

相关讨论

使用json.net库，您可以从nuget包管理器下载它。

序列化为JSON字符串：

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var obj = new Lad
{
firstName ="Markoff",
lastName ="Chaney",
dateOfBirth = new MyDate
{
year = 1901,
month = 4,
day = 30
}
};

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

正在反序列化到对象：

1	var obj = Newtonsoft.Json.JsonConvert.DeserializeObject<Lad>(jsonString );

使用DataContractJsonSerializer类：msdn1、msdn2。

我的例子：这里。

它还可以从JSON字符串安全地反序列化对象，与JavaScriptSerializer不同。但我个人还是喜欢json.net。

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Wooou！使用JSON框架更好：)

下面是我使用json.net(http://james.newtonking.com/json)的示例：

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<Address> 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<Address> 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<Address> addresses)
{
this.id = id;
this.name = personName;
this.addresses = addresses;
}

public Contact(String JSONRepresentation)
{
//To do
}
}
}

测试：

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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<Address> addresses = new List<Address>();
addresses.Add(new Address(1,"Rua Dr. Fernandes Coelho, 85","15o andar","S?o Paulo","S?o Paulo","Brazil","05423040"));
addresses.Add(new Address(2,"Avenida Senador Teot?nio Vilela, 241", null,"S?o Paulo","S?o Paulo","Brazil", null));

Contact contact = new Contact(1,"Ayrton Senna", addresses);

Console.WriteLine(contact.ToJSONRepresentation());
Console.ReadKey();
}
}
}

结果：

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

现在，我将实现构造函数方法，该方法将接收JSON字符串并填充类的字段。

相关讨论

如果它们不是很大，那么您的案例将其导出为JSON。这使得所有平台都可以移植

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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);
}

如果您使用的是ASP.NET MVC Web控制器，那么它的简单程度如下：

1	string ladAsJson = Json(Lad);

真不敢相信没人提到这件事。

相关讨论

使用此工具生成C类，然后使用此代码序列化对象

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

同样简单，也适用于动态对象(类型对象)：

1 2	string json = new System.Web.Script.Serialization.JavaScriptSerializer().Serialize(MYOBJECT);

相关讨论

使用下面的代码将XML转换为JSON。

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

我将投票支持ServiceStack的JSON序列化程序：

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using ServiceStack.Text

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

它也是.NET中最快的JSON序列化程序：http://www.servicestack.net/基准/

相关讨论

这里有一个非常漂亮的实用程序：http://csharp2json.io/

串行化器

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public static void WriteToJsonFile<T>(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);
}
}

对象

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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;
}
}

实施

1 2	var jsonObject = new AppConfigurationSettings(); WriteToJsonFile<AppConfigurationSettings>(file.FullName, jsonObject);

产量

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

还要注意创建具有正确属性的类：

根据示例c example后跟vb.net exmpale，使用属性创建此类

C.*

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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<Product> _ProductsList;
public List<Product> 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;
}

}

}

VBNET实例

Imports System
Imports System.Web
Imports System.Web.Script.Serialization
Namespace Samples
<Serializable()>
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

<Serializable()>
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

<Serializable>
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

结束命名空间

第二步是创建这样一个简单的测试数据：

C.*

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void Main() {
List<Samples.Product> ListProducts = new List<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);
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

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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

这是最后的结果：

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{"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"}

请记住添加对system.web.extension.dll的引用，以实现您的目标。

相关讨论