Newtonsoft.Json.Linq 常用方法总结

目录

• 1、entity to json
  • 1.2、entity to json
  • 1.3、json to entity
• 2、linq to json
  • 2.2、从 json 字符串创建 jobject
  • 2.3、从 entity 创建 jobject

1、entity to json

1.1、准备工作

我们以如下的 person 类举例，其中包含了常用的数据类型：

public class person
{
    public int id { get; set; }

    public string name { get; set; }

    public datetime birthday { get; set; }

    public bool isvip { get; set; }
    
    public float account { get; set; }

    public string[] favorites { get; set; }
    
    public string remark { get; set; }
}

创建一个 person 实例：

person person = new person
{
    id = 1,
    name = "张三",
    birthday = datetime.parse("2000-01-02"),
    isvip = true,
    account = 12.34f,
    favorites = new string[] { "吃饭", "睡觉" }
};

1.2、entity to json

返回不缩进的 json 字符串

jsonconvert.serializeobject(person)

返回：

{"id":1,"name":"张三","birthday":"2000-01-02t00:00:00","isvip":true,"account":12.34,"favorites":["吃饭","睡觉"],"remark":null}

返回缩进的 json 字符串

jsonconvert.serializeobject(person, formatting.indented);

返回：

{
    "id": 1,
    "name": "张三",
    "birthday": "2000-01-02t00:00:00",
    "isvip": true,
    "account": 12.34,
    "favorites": [
        "吃饭",
        "睡觉"
    ],
    "remark": null
}

json 字符串缩进

private string jsonindentation(string str)
{
    //string str = jsonconvert.serializeobject(entity);
    jsonserializer serializer = new jsonserializer();
    textreader tr = new stringreader(str);
    jsontextreader jtr = new jsontextreader(tr);
    object obj = serializer.deserialize(jtr);
    if (obj != null)
    {
        stringwriter textwriter = new stringwriter();
        jsontextwriter jsonwriter = new jsontextwriter(textwriter)
        {
            formatting = formatting.indented,
            indentation = 4,
            indentchar = ' '
        };
        serializer.serialize(jsonwriter, obj);
        return textwriter.tostring();
    }
    else
    {
        return str;
    }
}

或者：

private string jsonindentation(string json)
{
    jobject obj = jobject.parse(json);
    return obj.tostring();
}

其他设置

jsonserializersettings settings = new jsonserializersettings();
// 设置日期格式
settings.dateformatstring = "yyyy-mm-dd";
// 忽略空值
settings.nullvaluehandling = nullvaluehandling.ignore;
// 缩进
settings.formatting = formatting.indented;

jsonconvert.serializeobject(person, settings);

返回：

{
  "id": 1,
  "name": "张三",
  "birthday": "2000-01-02",
  "isvip": true,
  "account": 12.34,
  "favorites": [
    "吃饭",
    "睡觉"
  ]
}

1.3、json to entity

jsonconvert.deserializeobject<person>(json);

2、linq to json

2.1、创建对象

jobject obj = new jobject();
obj.add("id", 1);
obj.add("name", "张三");
obj.add("birthday", datetime.parse("2000-01-02"));
obj.add("isvip", true);
obj.add("account", 12.34f);
// 创建数组
jarray array = new jarray();
array.add(new jvalue("吃饭"));
array.add(new jvalue("睡觉"));
obj.add("favorites", array);
obj.add("remark", null);

2.2、从 json 字符串创建 jobject

string json = "{\"id\":1,\"name\":\"张三\",\"birthday\":\"2000-01-02t00:00:00\",\"isvip\":true,\"account\":12.34,\"favorites\":[\"吃饭\",\"睡觉\"],\"remark\":null}";

jobject obj = jobject.parse(json);

2.3、从 entity 创建 jobject

jobject obj = jobject.fromobject(person);

用匿名对象创建 jobject

jobject obj = jobject.fromobject(new { name = "jack", age = 18 });

显示：

{
  "name": "jack",
  "age": 18
}

2.2、获取值

int id;
if (obj["id"] != null)
    id = obj["id"].value<int>();

获取数组

newtonsoft.json.linq 不支持直接获取数组，但是可以获取 list，然后再转化为数组。

string[] favorites;
if (obj["favorites"] != null)
    favorites = obj["favorites"].value<list<string>>().toarray();