是否有方法将JSON内容反序列化为c#动态类型?为了使用DataContractJsonSerializer,最好跳过创建一堆类。


当前回答

在JSON中反序列化。NET可以使用包含在该库中的JObject类来实现动态。我的JSON字符串表示这些类:

public class Foo {
   public int Age {get;set;}
   public Bar Bar {get;set;}
}

public class Bar {
   public DateTime BDay {get;set;}
}

现在我们在不引用上述类的情况下反序列化字符串:

var dyn = JsonConvert.DeserializeObject<JObject>(jsonAsFooString);

JProperty propAge = dyn.Properties().FirstOrDefault(i=>i.Name == "Age");
if(propAge != null) {
    int age = int.Parse(propAge.Value.ToString());
    Console.WriteLine("age=" + age);
}

//or as a one-liner:
int myage = int.Parse(dyn.Properties().First(i=>i.Name == "Age").Value.ToString());

或者如果你想深入一点:

var propBar = dyn.Properties().FirstOrDefault(i=>i.Name == "Bar");
if(propBar != null) {
    JObject o = (JObject)propBar.First();
    var propBDay = o.Properties().FirstOrDefault (i => i.Name=="BDay");
    if(propBDay != null) {
        DateTime bday = DateTime.Parse(propBDay.Value.ToString());
        Console.WriteLine("birthday=" + bday.ToString("MM/dd/yyyy"));
    }
}

//or as a one-liner:
DateTime mybday = DateTime.Parse(((JObject)dyn.Properties().First(i=>i.Name == "Bar").First()).Properties().First(i=>i.Name == "BDay").Value.ToString());

完整的示例请参见文章。

其他回答

试试这种方法!

JSON的例子:

[{
    "id": 140,
    "group": 1,
    "text": "xxx",
    "creation_date": 123456,
    "created_by": "xxx@gmail.co",
    "tags": ["xxxxx"]
  }, {
    "id": 141,
    "group": 1,
    "text": "xxxx",
    "creation_date": 123456,
    "created_by": "xxx@gmail.com",
    "tags": ["xxxxx"]
}]

c#代码:

var jsonString = (File.ReadAllText(Path.Combine(Directory.GetCurrentDirectory(),"delete_result.json")));
var objects = JsonConvert.DeserializeObject<dynamic>(jsonString);
foreach(var o in objects)
{
    Console.WriteLine($"{o.id.ToString()}");
}

我做了一个使用Expando对象的DynamicJsonConverter的新版本。我使用了expando对象,因为我想使用Json.NET将动态序列化回JSON。

using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Dynamic;
using System.Web.Script.Serialization;

public static class DynamicJson
{
    public static dynamic Parse(string json)
    {
        JavaScriptSerializer jss = new JavaScriptSerializer();
        jss.RegisterConverters(new JavaScriptConverter[] { new DynamicJsonConverter() });

        dynamic glossaryEntry = jss.Deserialize(json, typeof(object)) as dynamic;
        return glossaryEntry;
    }

    class DynamicJsonConverter : JavaScriptConverter
    {
        public override object Deserialize(IDictionary<string, object> dictionary, Type type, JavaScriptSerializer serializer)
        {
            if (dictionary == null)
                throw new ArgumentNullException("dictionary");

            var result = ToExpando(dictionary);

            return type == typeof(object) ? result : null;
        }

        private static ExpandoObject ToExpando(IDictionary<string, object> dictionary)
        {
            var result = new ExpandoObject();
            var dic = result as IDictionary<String, object>;

            foreach (var item in dictionary)
            {
                var valueAsDic = item.Value as IDictionary<string, object>;
                if (valueAsDic != null)
                {
                    dic.Add(item.Key, ToExpando(valueAsDic));
                    continue;
                }
                var arrayList = item.Value as ArrayList;
                if (arrayList != null && arrayList.Count > 0)
                {
                    dic.Add(item.Key, ToExpando(arrayList));
                    continue;
                }

                dic.Add(item.Key, item.Value);
            }
            return result;
        }

        private static ArrayList ToExpando(ArrayList obj)
        {
            ArrayList result = new ArrayList();

            foreach (var item in obj)
            {
                var valueAsDic = item as IDictionary<string, object>;
                if (valueAsDic != null)
                {
                    result.Add(ToExpando(valueAsDic));
                    continue;
                }

                var arrayList = item as ArrayList;
                if (arrayList != null && arrayList.Count > 0)
                {
                    result.Add(ToExpando(arrayList));
                    continue;
                }

                result.Add(item);
            }
            return result;
        }

        public override IDictionary<string, object> Serialize(object obj, JavaScriptSerializer serializer)
        {
            throw new NotImplementedException();
        }

        public override IEnumerable<Type> SupportedTypes
        {
            get { return new ReadOnlyCollection<Type>(new List<Type>(new[] { typeof(object) })); }
        }
    }
}

我使用http://json2csharp.com/来获取表示JSON对象的类。

输入:

{
   "name":"John",
   "age":31,
   "city":"New York",
   "Childs":[
      {
         "name":"Jim",
         "age":11
      },
      {
         "name":"Tim",
         "age":9
      }
   ]
}

输出:

public class Child
{
    public string name { get; set; }
    public int age { get; set; }
}

public class Person
{
    public string name { get; set; }
    public int age { get; set; }
    public string city { get; set; }
    public List<Child> Childs { get; set; }
}

之后我使用Newtonsoft。Json填充类:

using Newtonsoft.Json;

namespace GitRepositoryCreator.Common
{
    class JObjects
    {
        public static string Get(object p_object)
        {
            return JsonConvert.SerializeObject(p_object);
        }
        internal static T Get<T>(string p_object)
        {
            return JsonConvert.DeserializeObject<T>(p_object);
        }
    }
}

你可以这样调用它:

Person jsonClass = JObjects.Get<Person>(stringJson);

string stringJson = JObjects.Get(jsonClass);

PS:

如果你的JSON变量名不是一个有效的c#名称(名称以$开头),你可以这样修复:

public class Exception
{
   [JsonProperty(PropertyName = "$id")]
   public string id { get; set; }
   public object innerException { get; set; }
   public string message { get; set; }
   public string typeName { get; set; }
   public string typeKey { get; set; }
   public int errorCode { get; set; }
   public int eventId { get; set; }
}

你可以扩展JavaScriptSerializer来递归复制它创建的字典来扩展对象,然后动态地使用它们:

static class JavaScriptSerializerExtensions
{
    public static dynamic DeserializeDynamic(this JavaScriptSerializer serializer, string value)
    {
        var dictionary = serializer.Deserialize<IDictionary<string, object>>(value);
        return GetExpando(dictionary);
    }

    private static ExpandoObject GetExpando(IDictionary<string, object> dictionary)
    {
        var expando = (IDictionary<string, object>)new ExpandoObject();

        foreach (var item in dictionary)
        {
            var innerDictionary = item.Value as IDictionary<string, object>;
            if (innerDictionary != null)
            {
                expando.Add(item.Key, GetExpando(innerDictionary));
            }
            else
            {
                expando.Add(item.Key, item.Value);
            }
        }

        return (ExpandoObject)expando;
    }
}

然后,您只需要为您在其中定义扩展的名称空间使用一个using语句(考虑在System.Web.Script.Serialization中定义它们…)另一个技巧是不使用命名空间,那么你根本不需要using语句),你可以像这样使用它们:

var serializer = new JavaScriptSerializer();
var value = serializer.DeserializeDynamic("{ 'Name': 'Jon Smith', 'Address': { 'City': 'New York', 'State': 'NY' }, 'Age': 42 }");

var name = (string)value.Name; // Jon Smith
var age = (int)value.Age;      // 42

var address = value.Address;
var city = (string)address.City;   // New York
var state = (string)address.State; // NY

我想在单元测试中以编程的方式完成,我可以把它打出来。

我的解决方案是:

var dict = JsonConvert.DeserializeObject<ExpandoObject>(json) as IDictionary<string, object>;

现在我可以断言

dict.ContainsKey("ExpectedProperty");