I am trying to deserialize multipart JSON message received from httpclient, but I have no experiences with the multipart message. The standard complex JSON is no problem thanks to newtonsoft, but I cant deserialize the multipart message. Is there a package or something for that. I dont want to create some complex code if no needed.

MESSAGE looks like:

*--------------------------70fc0426e01b4f98
Content-Disposition: form-data; name="event"; 
filename="0001_20220308194235_379109_event_5608_1642.json" 
Content-Type: application/octet-stream*

{"packetCounter":"5608",
"capture_timestamp":"1646764948776",
"frame_timestamp":"0",
"capture_ts":"1646764948776000000",
"datetime":"20220308 194228776",
"plateText":"\u0042\u0041\u0030\u0030\u0036\u0046\u0056",
"plateUnicode":"\u0042\u0041\u0030\u0030\u0036\u0046\u0056",
"plateUTF8":"SL006FV",
"plateASCII":"SL006FV",
"plateCountry":"UK",
"plateConfidence":"0.672017",
"carState":"lost",
"roiID":"1",
"geotag":{"lat": 50.418114,"lon": 30.476213},"imageType": "plate","plateImageType": "png","plateImageSize": "0","carMoveDirection":"in",
"timeProcessing":"0",
"plateCoordinates":[959, 246, 132, 28],
"plateCoordinatesRelative":[0, 0, 0, 0],
"carID":"1642",
"GEOtarget":"Camera",
"imagesURI":["/local/fflprapp/tools.cgi?action=getImage&name=7/20220308194229_354996lp_SL006FV_0.jpg","/local/fflprapp/tools.cgi?action=getImage&name=5/20220308194228_891633roi_SL006FV_0.jpg"],
"imageFile":"/tmp/FFLPR_MMCR/images/5/20220308194228_891633roi_SL006FV_0.jpg",
"camera_info":{"SerialNumber":"000000000000","ProdShortName":"Mobotix M73","MACAddress":"0003C5200D41"},
"sensorProviderID":"23"
}

*--------------------------70fc0426e01b4f98
Content-Disposition: form-data; name="image"; filename="20220308194228_891633roi_SL006FV_0.jpg"
Content-Type: image/jpeg*

CodePudding user response：

thanks for the quick response. Maybe I wrotte it wrong way. The JSON message itself is OK, I use the following code for the Async client.

I try to link the file from the message and display datas from JSON and picture from this.

filename="20220308194228_891633roi_SL006FV_0.jpg" Content-Type: image/jpeg

But I am as far as this and cant link 2 messages/headers if it is the multipart message.

TCPServerAsync class:

    internal class TCPServerAsync
    {

        private volatile bool stop = true;


        public async Task StartAsync(int port)
        {
            var prefix = "http://*:12321/";
            HttpListener listener = new HttpListener();
            listener.Prefixes.Add(prefix);

            try
            {
                listener.Start();
                stop = false;
            }
            catch (HttpListenerException hlex)
            {

                return;
            }
            while (listener.IsListening)
            {
                var context = await listener.GetContextAsync();    
            
                try
                {
                    await ProcessRequestAsync(context);
                }
                catch (Exception ex)
                {                        
                    return;
                }
                if (stop == true) listener.Stop();
            }
            listener.Close();
        }

        public void Stop()
        {
            stop = true;
        }

        private async Task ProcessRequestAsync(HttpListenerContext context)
        {                
            var body = await new StreamReader(context.Request.InputStream).ReadToEndAsync();
            HttpListenerRequest request = context.Request;

            byte[] b = Encoding.UTF8.GetBytes("ACK");
            context.Response.StatusCode = 200;
            context.Response.KeepAlive = false;
            context.Response.ContentLength64 = b.Length;                
            var output = context.Response.OutputStream;
            await output.WriteAsync(b, 0, b.Length);
            context.Response.Close();
        }

    }

  
}

Deserialize class

public Rootobject DeSerializeJSON(string JSONmessage)
        {

            Rootobject obj = JsonConvert.DeserializeObject<Rootobject>(JSONmessage);        
            return obj;
        }


        public class Rootobject
        {
            public string packetCounter { get; set; }
            public string capture_timestamp { get; set; }
            public string frame_timestamp { get; set; }
            public string capture_ts { get; set; }
            public string datetime { get; set; }
            public string plateText { get; set; }
            public string plateUnicode { get; set; }
            public string plateUTF8 { get; set; }
            public string plateASCII { get; set; }
            public string plateCountry { get; set; }
            public string plateConfidence { get; set; }
            public string carState { get; set; }
            public string roiID { get; set; }
            public Geotag geotag { get; set; }
            public string imageType { get; set; }
            public string plateImageType { get; set; }
            public string plateImageSize { get; set; }
            public string carMoveDirection { get; set; }
            public string timeProcessing { get; set; }
            public int[] plateCoordinates { get; set; }
            public int[] plateCoordinatesRelative { get; set; }
            public string carID { get; set; }
            public string GEOtarget { get; set; }
            public string[] imagesURI { get; set; }
            public string imageFile { get; set; }
            public Vehicle_Info vehicle_info { get; set; }
            public Camera_Info camera_info { get; set; }
            public string sensorProviderID { get; set; }
        }

        public class Geotag
        {
            public float lat { get; set; }
            public float lon { get; set; }
        }

        public class Vehicle_Info
        {
            public string brand { get; set; }
            public string model { get; set; }
            public string type { get; set; }
            public string color { get; set; }
            public string confidence { get; set; }
        }

        public class Camera_Info
        {
            public string SerialNumber { get; set; }
            public string ProdShortName { get; set; }
            public string MACAddress { get; set; }
        }
    }

CodePudding user response：

You can use JsonConvert.DeserializeObject for this.

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

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            string jsonText = File.ReadAllText(@"path\to\jsonFile.json");
            JObject jsonObject = JsonConvert.DeserializeObject<JObject>(jsonText);
            string packetCounter = jsonObject["packetCounter"].ToString();
        }
    }
}

In my example I'm getting the json text from a file. You just need to get it from the httpclient instead. Then you can deserialize it with JsonConvert.DeserializeObject into a JObject.