如何从C#中的JSON字符串中获取一些值？

Question

我有一个字符串,我想从中获取一些值.

我的字符串看起来像:

STRING1:

"{\r\n   \"id\": \"100000280905615\",
 \r\n \"name\": \"Jerard Jones\",
 \r\n   \"first_name\": \"Jerard\",
 \r\n   \"last_name\": \"Jones\",
 \r\n   \"link\": \"https://www.facebook.com/Jerard.Jones\",
 \r\n   \"username\": \"Jerard.Jones\",
 \r\n   \"gender\": \"female\",
 \r\n   \"locale\": \"en_US\"\r\n}"

字符串2:

"{\r\n   \"id\": \"100000390001929\",
  \r\n   \"name\": \"\\u05d1\\u05d2\\u05e8\\u15dc\\u25d9 \\u05d1\\u05e8\\u05d5\\u05e9\",
  \r\n   \"first_name\": \"\\u05d4\\u05d2\\u05e7\\u02dc\\u05d9\",
  \r\n   \"last_name\": \"\\u05d1\\u05e8\\u05d5\\u05e9\",
  \r\n   \"link\": "https://www.facebook.com/people/\\u05d2\\u05d1\\u05e@\\u05dc\\u05d9-\\u05d1\\u05e8\\u05d4\\u05e9/100000390001929\",
  \r\n   \"gender\": \"female\",
  \r\n   \"locale\": \"he_IL\"\r\n}"

不幸的是,有一种情况是字符串将采用相同的概念,但没有一些参数:

STRING3:

"{\r\n   \"id\": \"100000390001929\",
  \r\n   \"last_name\": \"\\u05d1\\u05e8\\u05d5\\u05e9\",
  \r\n   \"gender\": \"female\",
  \r\n   \"locale\": \"he_IL\"\r\n}"

我怎样才能得到的值:id,first_name,last_name,gender,locale？

任何帮助赞赏!

Answer 1

您的字符串是JSON格式的,因此您需要将其解析为对象.为此,您可以使用JSON.NET.

以下是如何将JSON字符串解析为动态对象的示例:

string source = "{\r\n   \"id\": \"100000280905615\", \r\n \"name\": \"Jerard Jones\",  \r\n   \"first_name\": \"Jerard\", \r\n   \"last_name\": \"Jones\", \r\n   \"link\": \"https://www.facebook.com/Jerard.Jones\", \r\n   \"username\": \"Jerard.Jones\", \r\n   \"gender\": \"female\", \r\n   \"locale\": \"en_US\"\r\n}";
dynamic data = JObject.Parse(source);
Console.WriteLine(data.id);
Console.WriteLine(data.first_name);
Console.WriteLine(data.last_name);
Console.WriteLine(data.gender);
Console.WriteLine(data.locale);

快乐的编码!

Answer 2

.NET 6 版本使用System.Text.Json

using System;
                    
public class Program
{
    public static void Main()
    {
        var jsonString = @"{ ""id"" : 123 }";
        
        //parse it
        var yourObject = System.Text.Json.JsonDocument.Parse(jsonString);
        //retrieve the value
        var id= yourObject.RootElement
                          .GetProperty("id");
        
        Console.WriteLine(id);
    }
}

要检索嵌套属性，您可以链接调用GetProperty。作为一个更高级的示例：

//access first element of array "persons" get nested property "age" 
var age = yourObject.rootElement.GetProperty("persons")[0]
                                .GetProperty("age");

Answer 3

我的字符串

var obj = {"Status":0,"Data":{"guid":"","invitationGuid":"","entityGuid":"387E22AD69-4910-430C-AC16-8044EE4A6B24443545DD"},"Extension":null}

以下代码获取 guid：

var userObj = JObject.Parse(obj);
var userGuid = Convert.ToString(userObj["Data"]["guid"]);

Answer 4

以下代码对我有用.

using System.IO;
using System.Net;
using Newtonsoft.Json.Linq;

Answer 5

创建一个这样的类:

public class Data
{
    public string Id {get; set;}
    public string Name {get; set;}
    public string First_Name {get; set;}
    public string Last_Name {get; set;}
    public string Username {get; set;}
    public string Gender {get; set;}
    public string Locale {get; set;}
}

(我不是100%肯定,但如果不工作,你就需要使用[DataContract]和[DataMember]对DataContractJsonSerializer.)

然后创建JSonSerializer:

private static readonly XmlObjectSerializer Serializer = new DataContractJsonSerializer(typeof(Data));

和反序列化对象:

// convert string to stream
byte[] byteArray = Encoding.UTF8.GetBytes(contents);
using(var stream = new MemoryStream(byteArray))
{
    (Data)Serializer.ReadObject(stream);
}