如何从 C # 中的 JSON 字符串中获取一些值?

我有一个字符串,我想从中得到一些值。

我的字符串看起来像:

字符串1:

"{\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,字符串由相同的概念构成,但是没有一些参数:

字符串3:

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

我如何得到的值: idfirst_namelast_namegenderlocale

感谢你们的帮助!

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Your strings are JSON formatted, so you will need to parse it into a object. For that you can use JSON.NET.

Here is an example on how to parse a JSON string into a dynamic object:

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);

Happy coding!

Create a class like this:

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;}
}

(I'm not 100% sure, but if that doesn't work you'll need use [DataContract] and [DataMember] for DataContractJsonSerializer.)

Then create JSonSerializer:

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

and deserialize object:

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

Following code is working for me.

Usings:

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

Code:

 using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
{
using (Stream responseStream = response.GetResponseStream())
{
using (StreamReader responseReader = new StreamReader(responseStream))
{
string json = responseReader.ReadToEnd();
string data = JObject.Parse(json)["id"].ToString();
}
}
}


//json = {"kind": "ALL", "id": "1221455", "longUrl": "NewURL"}

my string

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

Following code to get guid:

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

A .NET 6 version using 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);
}
}

To retrieve nested properties, you can chain the GetProperty calls. As a more advanced example:

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