如何使用C#反序列化JSON数据？

{
 "Items": [{
        "Name": "Apple",
        "Price": 12.3
    },
    {
        "Name": "Grape",
        "Price": 3.21
    }
   ],
   "Date": "21/11/2010"
}

那么，一旦你从NuGet安装了NewtonSoft.Json并将其包含在项目中，你就可以将其序列化为：

string jsonString = "{\"Items\": [{\"Name\": \"Apple\",\"Price\": 12.3},{\"Name\": \"Grape\",\"Price\": 3.21}],\"Date\": \"21/11/2010\"}";

        dynamic DynamicData = JsonConvert.DeserializeObject(jsonString);

        Console.WriteLine(   DynamicData.Date); // "21/11/2010"
        Console.WriteLine(DynamicData.Items.Count); // 2
        Console.WriteLine(DynamicData.Items[0].Name); // "Apple"

来源: 如何在C#中读取JSON数据（使用Console应用程序和ASP.NET MVC示例）？

JsonValue jsonValue = JsonValue.Parse("{\"Width\": 800, \"Height\": 600, \"Title\": \"View from 15th Floor\", \"IDs\": [116, 943, 234, 38793]}");
double width = jsonValue.GetObject().GetNamedNumber("Width");
double height = jsonValue.GetObject().GetNamedNumber("Height");
string title = jsonValue.GetObject().GetNamedString("Title");
JsonArray ids = jsonValue.GetObject().GetNamedArray("IDs");

nuget install Microsoft.AspNet.WebApi.Core
nuget install Microsoft.Net.Http
nuget install Newtonsoft.Json

代码：

using Newtonsoft.Json;
using System;
using System.Net.Http;
using System.Threading.Tasks;

public static class App
{
    static void Main()
    {
        MainAsync().GetAwaiter().GetResult();
    }

    static async Task MainAsync()
    {
        string url = "https://httpbin.org/get";
        var client = new HttpClient();

        // The verbose way:
        //HttpResponseMessage response = await client.GetAsync(url);
        //response.EnsureSuccessStatusCode();
        //string responseBody = await response.Content.ReadAsStringAsync();

        // Or:
        string responseBody = await client.GetStringAsync(url);

        var obj = JsonConvert.DeserializeObject<dynamic>(responseBody);
        Console.WriteLine(obj);
        Console.WriteLine(obj.headers.Host);
    }
}

编译命令：

 csc http_request2.cs -r:".\Microsoft.AspNet.WebApi.Core.5.2.9\lib\net45\System.Web.Http.dll" -r:".\Microsoft.Net.Http.2.2.29\lib\net40\System.Net.Http.dll" -r:".\Newtonsoft.Json.13.0.1\lib\net45\Newtonsoft.Json.dll"

输出：

{
  "args": {},
  "headers": {
    "Host": "httpbin.org",
    "X-Amzn-Trace-Id": "Root=1-633dce52-64f923bb42c99bf46f78672c"
  },
  "origin": "98.51.7.199",
  "url": "https://httpbin.org/get"
}
httpbin.org

你可以在这里找到它：

https://github.com/starnutoditopo/JsonToObject

JsonToObjectConverter.cs

using System.Globalization;
using System.Reflection;
using System.Reflection.Emit;
using System.Text.Json;

namespace JsonToObject;

/// <summary>Provides functionalities to convert JSON strings in to CLR objects.</summary>
public class JsonToObjectConverter
{
    private class Counter
    {
        private ulong count;
        public Counter()
        {
            this.count = 0;
        }

        public ulong Next()
        {
            this.count++;
            return this.count;
        }
    }


    private static ulong assemblyGenerationCounter;
    private readonly JsonToObjectConverterOptions options;

    static JsonToObjectConverter()
    {
        assemblyGenerationCounter = 0;
    }

    /// <summary>
    /// Initializes a new instance of the <see cref="JsonToObjectConverter" /> class, using default options.
    /// </summary>
    /// <param name="options">The options.</param>
    public JsonToObjectConverter()
        : this(new JsonToObjectConverterOptions())
    {
    }


    /// <summary>
    /// Initializes a new instance of the <see cref="JsonToObjectConverter" /> class, using the specified options.
    /// </summary>
    /// <param name="options">The options.</param>
    public JsonToObjectConverter(JsonToObjectConverterOptions options)
    {
        this.options = options;
    }

    /// <summary>Converts a JSON string to an instance of a CLR object.</summary>
    /// <param name="jsonString">The json string.</param>
    /// <returns>
    ///   <br />
    /// </returns>
    public object? ConvertToObject(string jsonString)
    {
        JsonSerializerOptions opt = new JsonSerializerOptions()
        {
            PropertyNameCaseInsensitive = true
        };
        JsonElement rawResult = JsonSerializer.Deserialize<JsonElement>(jsonString, opt);
        object? result = ToStronglyTypedObject(rawResult);
        return result;
    }

    private object? ToStronglyTypedObject(JsonElement? nullableJsonElement)
    {
        string assemblyNameString;
        ulong assemblyId = Interlocked.Increment(ref assemblyGenerationCounter);
        try
        {
            assemblyNameString = string.Format(this.options.RuntimeGeneratedAssemblyNameTemplate, assemblyId.ToString(CultureInfo.InvariantCulture));
        }
        catch
        {
            throw new InvalidOperationException($@"Unable to generate assembly name using template '{this.options.RuntimeGeneratedAssemblyNameTemplate}' and id '{assemblyId}'. Please, review the {nameof(JsonToObjectConverterOptions.RuntimeGeneratedAssemblyNameTemplate)} property in the options.");
        }
        ModuleBuilder moduleBuilder = CreateModuleBuilder(assemblyNameString, this.options.RuntimeGeneratedModuleName);
        Counter typeGenerationCounter = new Counter();
        var result = ToStronglyTypedObject(nullableJsonElement, moduleBuilder, typeGenerationCounter);
        return result;
    }
    private object? ToStronglyTypedObject(
        JsonElement? nullableJsonElement,
        ModuleBuilder moduleBuilder,
        Counter typeGenerationCounter
    )
    {
        if (nullableJsonElement == null)
        {
            return null;
        }

        JsonElement jsonElement = nullableJsonElement.Value;

        switch (jsonElement.ValueKind)
        {
            case JsonValueKind.Undefined:
                return null;
            case JsonValueKind.String:
                return jsonElement.GetString();
            case JsonValueKind.False:
                return false;
            case JsonValueKind.True:
                return true;
            case JsonValueKind.Null:
                return null;
            case JsonValueKind.Number:
                {
                    if (jsonElement.TryGetDouble(out var result))
                    {
                        return result;
                    }
                }
                throw new InvalidOperationException($"Unable to parse {jsonElement} as number.");
            case JsonValueKind.Object:
                {
                    ulong typeId = typeGenerationCounter.Next();
                    string typeName;
                    try
                    {
                        typeName = string.Format(this.options.RuntimeGeneratedTypeNameTemplate, typeId.ToString(CultureInfo.InvariantCulture));
                    }
                    catch
                    {
                        throw new InvalidOperationException($@"Unable to generate type name using template '{this.options.RuntimeGeneratedTypeNameTemplate}' and id '{typeId}'. Please, review the {nameof(JsonToObjectConverterOptions.RuntimeGeneratedTypeNameTemplate)} property in the options.");
                    }

                    TypeBuilder typeBuilder = CreateTypeBuilder(moduleBuilder, typeName);
                    Dictionary<string, object?> propertyValues = new Dictionary<string, object?>();
                    foreach (var property in jsonElement.EnumerateObject())
                    {
                        string propertyName = property.Name;
                        object? propertyValue = ToStronglyTypedObject(property.Value, moduleBuilder, typeGenerationCounter);
                        Type propertyValueType;
                        if (null == propertyValue)
                        {
                            propertyValueType = typeof(object);
                        }
                        else
                        {
                            propertyValueType = propertyValue.GetType();
                        }
                        CreateAutoImplementedProperty(typeBuilder, propertyName, propertyValueType);
                        propertyValues.Add(propertyName, propertyValue);
                    }

                    Type resultType = typeBuilder.CreateType()!;
                    object result = Activator.CreateInstance(resultType)!;
                    foreach (var pair in propertyValues)
                    {
                        var propertyInfo = resultType.GetProperty(pair.Key)!;
                        propertyInfo.SetValue(result, pair.Value);
                    }
                    return result;
                }
            case JsonValueKind.Array:
                {
                    List<object?> list = new List<object?>();
                    foreach (var item in jsonElement.EnumerateArray())
                    {
                        object? value = ToStronglyTypedObject(item, moduleBuilder, typeGenerationCounter);
                        list.Add(value);
                    }
                    return list.ToArray();
                }
            default:
                throw new InvalidOperationException($"Value type '{jsonElement.ValueKind}' is not supported");
        }
    }

    private static ModuleBuilder CreateModuleBuilder(
            string assemblyNameString,
            string moduleName
        )
    {
        // create assembly name
        var assemblyName = new AssemblyName(assemblyNameString);
        // create the assembly builder
        AssemblyBuilder assemblyBuilder = AssemblyBuilder.DefineDynamicAssembly(assemblyName, AssemblyBuilderAccess.Run);

        // create the module builder
        ModuleBuilder moduleBuilder = assemblyBuilder.DefineDynamicModule(moduleName);
        return moduleBuilder;
    }

    private static TypeBuilder CreateTypeBuilder(
            ModuleBuilder moduleBuilder,
            string typeName
        )
    {
        // create the type builder
        TypeBuilder typeBuilder = moduleBuilder.DefineType(typeName, TypeAttributes.Public);
        typeBuilder.DefineDefaultConstructor(MethodAttributes.Public);
        return typeBuilder;
    }

    private static void CreateAutoImplementedProperty(
        TypeBuilder builder,
        string propertyName,
        Type propertyType
        )
    {
        const string PrivateFieldPrefix = "m_";
        const string GetterPrefix = "get_";
        const string SetterPrefix = "set_";

        // Generate the field.
        FieldBuilder fieldBuilder = builder.DefineField(
            string.Concat(PrivateFieldPrefix, propertyName),
                          propertyType, FieldAttributes.Private);

        // Generate the property
        PropertyBuilder propertyBuilder = builder.DefineProperty(
            propertyName, PropertyAttributes.HasDefault, propertyType, null);

        // Property getter and setter attributes.
        MethodAttributes propertyMethodAttributes =
            MethodAttributes.Public | MethodAttributes.SpecialName |
            MethodAttributes.HideBySig;

        // Define the getter method.
        MethodBuilder getterMethod = builder.DefineMethod(
            string.Concat(GetterPrefix, propertyName),
            propertyMethodAttributes, propertyType, Type.EmptyTypes);

        // Emit the IL code.
        // ldarg.0
        // ldfld,_field
        // ret
        ILGenerator getterILCode = getterMethod.GetILGenerator();
        getterILCode.Emit(OpCodes.Ldarg_0);
        getterILCode.Emit(OpCodes.Ldfld, fieldBuilder);
        getterILCode.Emit(OpCodes.Ret);

        // Define the setter method.
        MethodBuilder setterMethod = builder.DefineMethod(
            string.Concat(SetterPrefix, propertyName),
            propertyMethodAttributes, null, new Type[] { propertyType });

        // Emit the IL code.
        // ldarg.0
        // ldarg.1
        // stfld,_field
        // ret
        ILGenerator setterILCode = setterMethod.GetILGenerator();
        setterILCode.Emit(OpCodes.Ldarg_0);
        setterILCode.Emit(OpCodes.Ldarg_1);
        setterILCode.Emit(OpCodes.Stfld, fieldBuilder);
        setterILCode.Emit(OpCodes.Ret);

        propertyBuilder.SetGetMethod(getterMethod);
        propertyBuilder.SetSetMethod(setterMethod);
    }
}

JsonToObjectConverterOptions.cs

namespace JsonToObject;

/// <summary>
/// Defines the options to instantiate a <see cref="JsonToObjectConverter" /> object.
/// </summary>
public class JsonToObjectConverterOptions
{
    private const string CONSTANTS_RuntimeGeneratedModuleName = $"RuntimeGeneratedModule";
    private const string CONSTANTS_RuntimeGeneratedAssemblyNameTemplate = "RuntimeGeneratedAssembly_{0}";
    private const string CONSTANTS_RuntimeGeneratedTypeNameTemplate = "RuntimeGeneratedType_{0}";

    /// <summary>Gets or sets the name of the runtime-generated module.</summary>
    /// <value>The name of the runtime-generated module.</value>
    public string RuntimeGeneratedModuleName { get; set; } = CONSTANTS_RuntimeGeneratedModuleName;

    /// <summary>Gets or sets the template to use to generate the name of runtime-generated assemblies.</summary>
    /// <value>The template to use to generate the name of runtime-generated assemblies.</value>
    /// <remarks>Should contain a "{0}" placeholder.</remarks>
    public string RuntimeGeneratedAssemblyNameTemplate { get; set; } = CONSTANTS_RuntimeGeneratedAssemblyNameTemplate;

    /// <summary>Gets or sets the template to use to generate the name of runtime-generated types.</summary>
    /// <value>The template to use to generate the name of runtime-generated types.</value>
    /// <remarks>Should contain a "{0}" placeholder.</remarks>
    public string RuntimeGeneratedTypeNameTemplate { get; set; } = CONSTANTS_RuntimeGeneratedTypeNameTemplate;
}

您可以使用以下扩展名

public static class JsonExtensions
{
    public static T ToObject<T>(this string jsonText)
    {
        return JsonConvert.DeserializeObject<T>(jsonText);
    }

    public static string ToJson<T>(this T obj)
    {
        return JsonConvert.SerializeObject(obj);
    } 
}

我认为我看到的最好的答案是@MD_Sayem_Ahmed。

你的问题是“如何使用C#解析Json”，但似乎你想要解码Json。如果你想要解码它，Ahmed的答案很好。

如果你想在ASP.NET Web Api中完成这个任务，最简单的方法是创建一个数据传输对象来保存你想要分配的数据：

public class MyDto{
    public string Name{get; set;}
    public string Value{get; set;}
}

你只需在请求中添加application/json头（例如，如果你使用Fiddler）。 然后，在ASP.NET Web API中使用如下：

//controller method -- assuming you want to post and return data
public MyDto Post([FromBody] MyDto myDto){
   MyDto someDto = myDto;
   /*ASP.NET automatically converts the data for you into this object 
    if you post a json object as follows:
{
    "Name": "SomeName",
      "Value": "SomeValue"
}
*/
   //do some stuff
}

这对我在工作中使用 Web Api 时帮助很大，使我的工作变得轻松愉快。

         string json = @"{
            'Name': 'Wide Web',
            'Url': 'www.wideweb.com.br'}";

        JavaScriptSerializer jsonSerializer = new JavaScriptSerializer();
        dynamic j = jsonSerializer.Deserialize<dynamic>(json);
        string name = j["Name"].ToString();
        string url = j["Url"].ToString();

var result = controller.ActioName(objParams);
IDictionary<string, object> data = (IDictionary<string, object>)new System.Web.Routing.RouteValueDictionary(result.Data);
Assert.AreEqual("Table already exists.", data["Message"]);

 using (var ms = new MemoryStream(Encoding.Unicode.GetBytes(user)))
 {
    // Deserialization from JSON  
    DataContractJsonSerializer deserializer = new DataContractJsonSerializer(typeof(UserListing))
    DataContractJsonSerializer(typeof(UserListing));
    UserListing response = (UserListing)deserializer.ReadObject(ms);

 }

 public class UserListing
 {
    public List<UserList> users { get; set; }      
 }

 public class UserList
 {
    public string FirstName { get; set; }       
    public string LastName { get; set; } 
 }