Parsing json objects

2019-01-14 18:10发布

问题:

I'm having trouble understanding how to parse JSON string into c# objects with Visual .NET. The task is very easy, but I'm still lost... I get this string:

{"single_token":"842269070","username":"example123","version":1.1}

And this is the code where I try to desterilize:

namespace _SampleProject
{
    public partial class Downloader : Form
    {
        public Downloader(string url, bool showTags = false)
        {
            InitializeComponent();
            WebClient client = new WebClient();
            string jsonURL = "http://localhost/jev";   
            source = client.DownloadString(jsonURL);
            richTextBox1.Text = source;
            JavaScriptSerializer parser = new JavaScriptSerializer();
            parser.Deserialize<???>(source);
        }

I don't know what to put between the '<' and '>', and from what I've read online I have to create a new class for it..? Also, how do I get the output? An example would be helpful!

回答1:

Create a new class that your JSON can be deserialized into such as:

public class UserInfo
{
    public string single_token { get; set; }
    public string username { get; set; }
    public string version { get; set; }
}

public partial class Downloader : Form
{
    public Downloader(string url, bool showTags = false)
    {
        InitializeComponent();
        WebClient client = new WebClient();
        string jsonURL = "http://localhost/jev";
        source = client.DownloadString(jsonURL);
        richTextBox1.Text = source;
        JavaScriptSerializer parser = new JavaScriptSerializer();
        var info = parser.Deserialize<UserInfo>(source);

        // use deserialized info object
    }
}


回答2:

If you're using .NET 4 - use the dynamic datatype.

http://msdn.microsoft.com/en-us/library/dd264736.aspx

string json = "{ single_token:'842269070', username: 'example123', version:1.1}";

     JavaScriptSerializer jss = new JavaScriptSerializer();

     dynamic obj = jss.Deserialize<dynamic>(json);

     Response.Write(obj["single_token"]);
     Response.Write(obj["username"]);
     Response.Write(obj["version"]); 


回答3:

Yes, you need a new class with properties that will match your JSON.

MyNewClass result = parser.Deserialize<MyNewClass>(source);


回答4:

The usual way would be create a class (or a set of classes, for more complex JSON strings) that describes the object you want to deserialize and use that as the generic parameter.

Another option is to deserialize the JSON into a Dictionary<string, object>:

parser.Deserialize<Dictionary<string, object>>(source);

This way, you can access the data, but I wouldn't suggest you to do this unless you have to.



回答5:

You need a Class that match with the JSON you are getting and it will return a new object of that class with the values populated.



回答6:

Following is the code..

ServicePointManager.ServerCertificateValidationCallback = new System.Net.Security.RemoteCertificateValidationCallback(AcceptAllCertifications);

        request = WebRequest.Create("https://myipaddress/api/admin/configuration/v1/conference/1/");

        request.Credentials = new NetworkCredential("admin", "admin123");
        // Create POST data and convert it to a byte array.
        request.Method = "GET";          

                // Set the ContentType property of the WebRequest.
        request.ContentType = "application/json; charset=utf-8";          


        WebResponse response = request.GetResponse();
        // Display the status.
        Console.WriteLine(((HttpWebResponse)response).StatusDescription);
        // Get the stream containing content returned by the server.
        dataStream = response.GetResponseStream();
        // Open the stream using a StreamReader for easy access.
        StreamReader reader = new StreamReader(dataStream);
        // Read the content.
        string responseFromServer = reader.ReadToEnd();
        JavaScriptSerializer js = new JavaScriptSerializer();
        var obj = js.Deserialize<dynamic>(responseFromServer);
        Label1.Text = obj["name"];
        // Display the content.
        Console.WriteLine(responseFromServer);
        // Clean up the streams.
        reader.Close();
        dataStream.Close();
        response.Close();


回答7:

dynamic data = JObject.Parse(jsString);
var value= data["value"];