Newtonsoft.Json 常规用法

从 NuGet 安装 Newtonsoft.Json

Install-Package Newtonsoft.Json

常用using

using Newtonsoft.Json;
using Newtonsoft.Json.Linq;

.net core

--安装
Install-Package  Microsoft.AspNetCore.Mvc.NewtonsoftJson    

-Add    
public void ConfigureServices(IServiceCollection services)
{
    services.AddControllers().AddNewtonsoftJson();
}

序列化

//序列化  对象 -> JSON 字符串
string json = JsonConvert.SerializeObject(object);

//分序列化 JSON 字符串 -> 对象
var jsonObj = JsonConvert.DeserializeObject<object>(json);

通过对象直接获取字符串：复制对象，然后打开LINQPad 开，然后试用快捷键 Shfit+Alt+V 即可获取字符串。

--对象
{"code":0,"msg":"success","data":{"total":3,"details":{"codes":["1","2","3"]}}}
--字符串
"{\"code\":0,\"msg\":\"success\",\"data\":{\"total\":3,\"details\":{\"codes\":[\"1\",\"2\",\"3\"]}}}"

特性

[JsonProperty("student")]//重命名属性名
[JsonIgnore]//序列化时忽略此字段
[DisplayName("学生")]
//[JsonConverter(typeof(StringTruncatingConverter))]
public string Student { get; set; }

JObject、JArray、JProperty、JValue 的使用

JObject用来生成一个JSON对象{}
JArray用来生成一个JSON数组[]
JProperty用来生成一个JSON数据key:value
JValue则直接生成一个JSON值

创建json对象

把JObject理解为C#中的一个类，那么JProperty就是它的属性

--案例1

            var jObject = new
            {
                msg = "success",
                data = new
                {
                    total = 1,
                    diff = new int[3] { 1, 2, 3 }
                }

            };
            Console.WriteLine(JsonConvert.SerializeObject(jObject));

 输出

{
    "msg": "success",
    "data": {
        "total": 1,
        "diff": [1, 2, 3]
    }
}

--案例2

            var jobject = new JObject();
            jobject.Add(new JProperty("name", "jack"));
            jobject.Add(new JProperty("age", "28"));
            jobject.Add(new JProperty("content", new JObject(new JProperty("hobby", "game"))));
            Console.WriteLine(jobject);

输出

{
  "name": "jack",
  "age": "28",
  "content": {
    "hobby": "game"
  }
}

--案例3

    var jobject = new JObject { new JProperty("name", "renee"), new JProperty("age", 30) };

输出

{
  "name": "renee",
  "age": 30
}

--案例4

            JArray array = new JArray();
            array.Add("GongHui Linq");
            array.Add(new DateTime(2015, 12, 14));
            var jobject = new JObject();
            jobject.Add(new JProperty("name", "jack"));
            jobject.Add(new JProperty("age", "28"));
            jobject.Add(new JProperty("content", new JObject(new JProperty("hobby", "game"))));
            jobject["myArray"] = array;
            var jarray = new JArray();
            jarray.Add(jobject);
            jarray.Add(new JObject(new JProperty("name", "renne")));
            Console.WriteLine(jarray);

输出

[
  {
    "name": "jack",
    "age": "28",
    "content": {
      "hobby": "game"
    },
    "myArray": [
      "GongHui Linq",
      "2015-12-14T00:00:00"
    ]
  },
  {
    "name": "renne"
  }
]

解析json对象

--案例1

            var json = "{\"msg\":\"success\",\"code\":200,\"data\":\"data\"}";

            var jobject = JObject.Parse(json);

            //获取msg对象的值
            Console.WriteLine(jobject.Value<string>("msg"));
            Console.WriteLine(jobject["msg"]);

            //获取code对象的值
            Console.WriteLine(jobject.GetValue("code"));

            //判断对象是否存在
            if (jobject.ContainsKey("code") && jobject.Value<string>("code").Equals("200"))
            {
                Console.WriteLine("true");
            }
            else
            {
                Console.WriteLine("false");
            }

输出

success
success
200
True

 --案例2

            //创建一个对象
            var Object = new
            {
                code = 0,
                msg = "success",
                data = new
                {
                    total = 3,
                    details = new { codes = new string[] { "1", "2", "3" } }
                }
            };
            //对象转字符串
            var json = JsonConvert.SerializeObject(Object);
            //输出json
            Console.WriteLine(json);
            //解析对象
            var jObject = JObject.Parse(json);
            var jArray = JArray.Parse(jObject["data"]["details"]["codes"].ToString());
            //JArray转换对象
            var list = jArray.ToObject<string[]>();
            foreach (var item in list)
                Console.WriteLine(item);

输出

{
    "code": 0,
    "msg": "success",
    "data": {
        "total": 3,
        "details": {
            "codes": ["1", "2", "3"]
        }
    }
}
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原文地址：https://www.cnblogs.com/RainFate/p/15702842.html