C#•7d ago

✅ Opening a Json file

I switched from Newtonsoft.Json to System.Text.Json and i can't get it to work. it gives me an object with null attributes

38 Replies

FusedQyou•7d ago

If you want help you will have to give a lot more context than this and $paste your code for starters. This is incredibly vague and we don't know your project.

MODiX•7d ago

If your code is too long, you can post to https://paste.mod.gg/, save, and copy the link into chat for others to see your shared code!

FriteOP•7d ago

public static Ogmo.Level LoadLevel(string name)
{
    string file;
    using (StreamReader sr = new StreamReader(Path + name))
        file = sr.ReadToEnd();

    JsonSerializerOptions options = new JsonSerializerOptions();
    options.Converters.Add(new Converter());

    return JsonSerializer.Deserialize<Ogmo.Level>(file, options);
}

public static Ogmo.Level LoadLevel(string name)
{
    string file;
    using (StreamReader sr = new StreamReader(Path + name))
        file = sr.ReadToEnd();

    JsonSerializerOptions options = new JsonSerializerOptions();
    options.Converters.Add(new Converter());

    return JsonSerializer.Deserialize<Ogmo.Level>(file, options);
}

FusedQyou•7d ago

More code. Classes, the converter, everything related

SG97•7d ago

and how is Ogmo.Level looking?

FusedQyou•7d ago

This still helps nothing

FriteOP•7d ago

with Newtonsoft it worked

FusedQyou•7d ago

Which is an entirely different package

FriteOP•7d ago

my objects matchs the json file

FusedQyou•7d ago

The only suggestion I have now is that you validate that file actually contains the JSON you expect to deserialize. This could also be the cause of the problem. Until that, either check that or share the code or we have absolutely no way or reason to help Generally Newtonsoft and STJ work similary to eachother but there are plenty of factors that can influence it. The converter can be one of them. We can't help you with just pure guesswork so you should share the code or perform basic debugging.

FriteOP•7d ago

file:

{
  "ogmoVersion": "3.4.0",
  "width": 448,
  "height": 128,
  "offsetX": 0,
  "offsetY": 0,
  "values": {"BPM": 140},
  "layers": [
    {
      "name": "1",
      "_eid": "74127826",
      "offsetX": 0,
      "offsetY": 0,
      "gridCellWidth": 16,
      "gridCellHeight": 16,
      "gridCellsX": 28,
      "gridCellsY": 8,
      "entities": [
        {
          "name": "Kick",
          "id": 8,
          "_eid": "74122737",
          "x": 128,
          "y": 0,
          "originX": 0,
          "originY": 0,
          "values": {"IN": 1, "OUT": 0, "Random": true, "PositionX": 0}
        },
        {
          "name": "Kick",
          "id": 9,
          "_eid": "74122737",
          "x": 192,
          "y": 0,
          "originX": 0,
          "originY": 0,
          "values": {"IN": 1, "OUT": 0, "Random": true, "PositionX": 0}
        },
        {
          "name": "Kick",
          "id": 10,
          "_eid": "74122737",
          "x": 256,
          "y": 0,
          "originX": 0,
          "originY": 0,
          "values": {"IN": 1, "OUT": 0, "Random": true, "PositionX": 0}
        },
        {
          "name": "Kick",
          "id": 11,
          "_eid": "74122737",
          "x": 320,
          "y": 0,
          "originX": 0,
          "originY": 0,
          "values": {"IN": 1, "OUT": 0, "Random": true, "PositionX": 0}
        }
      ]
    },
    {
      "name": "2",
      "_eid": "74123146",
      "offsetX": 0,
      "offsetY": 0,
      "gridCellWidth": 16,
      "gridCellHeight": 16,
      "gridCellsX": 28,
      "gridCellsY": 8,
      "entities": []
    },
    {
      "name": "3",
      "_eid": "74121771",
      "offsetX": 0,
      "offsetY": 0,
      "gridCellWidth": 16,
      "gridCellHeight": 16,
      "gridCellsX": 28,
      "gridCellsY": 8,
      "entities": []
    }
  ]
}

{
  "ogmoVersion": "3.4.0",
  "width": 448,
  "height": 128,
  "offsetX": 0,
  "offsetY": 0,
  "values": {"BPM": 140},
  "layers": [
    {
      "name": "1",
      "_eid": "74127826",
      "offsetX": 0,
      "offsetY": 0,
      "gridCellWidth": 16,
      "gridCellHeight": 16,
      "gridCellsX": 28,
      "gridCellsY": 8,
      "entities": [
        {
          "name": "Kick",
          "id": 8,
          "_eid": "74122737",
          "x": 128,
          "y": 0,
          "originX": 0,
          "originY": 0,
          "values": {"IN": 1, "OUT": 0, "Random": true, "PositionX": 0}
        },
        {
          "name": "Kick",
          "id": 9,
          "_eid": "74122737",
          "x": 192,
          "y": 0,
          "originX": 0,
          "originY": 0,
          "values": {"IN": 1, "OUT": 0, "Random": true, "PositionX": 0}
        },
        {
          "name": "Kick",
          "id": 10,
          "_eid": "74122737",
          "x": 256,
          "y": 0,
          "originX": 0,
          "originY": 0,
          "values": {"IN": 1, "OUT": 0, "Random": true, "PositionX": 0}
        },
        {
          "name": "Kick",
          "id": 11,
          "_eid": "74122737",
          "x": 320,
          "y": 0,
          "originX": 0,
          "originY": 0,
          "values": {"IN": 1, "OUT": 0, "Random": true, "PositionX": 0}
        }
      ]
    },
    {
      "name": "2",
      "_eid": "74123146",
      "offsetX": 0,
      "offsetY": 0,
      "gridCellWidth": 16,
      "gridCellHeight": 16,
      "gridCellsX": 28,
      "gridCellsY": 8,
      "entities": []
    },
    {
      "name": "3",
      "_eid": "74121771",
      "offsetX": 0,
      "offsetY": 0,
      "gridCellWidth": 16,
      "gridCellHeight": 16,
      "gridCellsX": 28,
      "gridCellsY": 8,
      "entities": []
    }
  ]
}

my code:

using System;
using System.IO;
using System.Text.Json;

namespace JSABlike;

public abstract class Ogmo
{
    /*    for later
    public abstract class A
    {
        public float IN;
        public float OUT;
        public bool Random;
    }

    public class Bass : A
    {
        public float HOLD;
    }
    */

    public class LevelValues
    {
        public byte BPM;
    }

    public class Kick
    {
        public float IN;
        public float OUT;
        public bool Random;
        public short PositionX;
    }

    public class Entity
    {
        public string name;
        public uint id;
        public uint _eid;
        public ulong x;
        public uint y;
        public int originX;
        public int originY;
        public Kick values;
    }

    public class Layer
    {
        string name;
        string _eid;
        public int offsetX;
        public int offsetY;
        public byte gridCellWidth;
        public byte gridCellHeight;
        public uint gridCellsX;
        public uint gridCellsY;
        public Entity[] entities;
    }

    public class Level
    {
        public string ogmoVersion;
        public uint width;
        public uint height;
        public int offsetX;
        public int offsetY;
        public LevelValues values;
        public Layer[] layers;
    }
}

public static class LevelReader
{
    private static string Path => AppContext.BaseDirectory;

    public static Ogmo.Level LoadLevel(string name)
    {
        string file;
        using (StreamReader sr = new StreamReader(Path + name))
            file = sr.ReadToEnd();

        return JsonSerializer.Deserialize<Ogmo.Level>(file);
    }
}

using System;
using System.IO;
using System.Text.Json;

namespace JSABlike;

public abstract class Ogmo
{
    /*    for later
    public abstract class A
    {
        public float IN;
        public float OUT;
        public bool Random;
    }

    public class Bass : A
    {
        public float HOLD;
    }
    */

    public class LevelValues
    {
        public byte BPM;
    }

    public class Kick
    {
        public float IN;
        public float OUT;
        public bool Random;
        public short PositionX;
    }

    public class Entity
    {
        public string name;
        public uint id;
        public uint _eid;
        public ulong x;
        public uint y;
        public int originX;
        public int originY;
        public Kick values;
    }

    public class Layer
    {
        string name;
        string _eid;
        public int offsetX;
        public int offsetY;
        public byte gridCellWidth;
        public byte gridCellHeight;
        public uint gridCellsX;
        public uint gridCellsY;
        public Entity[] entities;
    }

    public class Level
    {
        public string ogmoVersion;
        public uint width;
        public uint height;
        public int offsetX;
        public int offsetY;
        public LevelValues values;
        public Layer[] layers;
    }
}

public static class LevelReader
{
    private static string Path => AppContext.BaseDirectory;

    public static Ogmo.Level LoadLevel(string name)
    {
        string file;
        using (StreamReader sr = new StreamReader(Path + name))
            file = sr.ReadToEnd();

        return JsonSerializer.Deserialize<Ogmo.Level>(file);
    }
}

SG97•7d ago

I can see public fields how's the converter looking

FusedQyou•7d ago

Pretty sure even Newtonsoft doesn't use public fields by default so this is something you configured

SG97•7d ago

think so too

FusedQyou•7d ago

STJ also has this configured. They use properties by default

FriteOP•7d ago

how should i make my objects ?

SG97•7d ago

can you show the converter generally I do public properties wait, there is no converter

FriteOP•7d ago

i removed it, first i just want it to load this

FusedQyou•7d ago

The correct answer would be to switch to properties since that's the correct approach. You can also pass configuration to System.Text.Json and specify fields should be used.

FusedQyou•7d ago

https://learn.microsoft.com/en-us/dotnet/standard/serialization/system-text-json/fields

Include fields in serialization - .NET

Learn how to include fields when you serialize to and deserialize from JSON in .NET.

FusedQyou•7d ago

https://learn.microsoft.com/en-us/dotnet/api/system.text.json.jsonserializeroptions.includefields?view=net-9.0#system-text-json-jsonserializeroptions-includefields

JsonSerializerOptions.IncludeFields Property (System.Text.Json)

Gets or sets a value that indicates whether fields are handled during serialization and deserialization. The default value is false.

SG97•7d ago

By default, fields are ignored. You can include fields. ah, I'm too slow

FriteOP•7d ago

um, is there a way to make them readonly or private set ? just to make things more clean

FusedQyou•7d ago

Make a property with a public getter but an init setter

FriteOP•7d ago

ahhh, i can't use uint ?

FusedQyou•7d ago

public int Foo { get; init; }

FriteOP•7d ago

i didn't know about that

FusedQyou•7d ago

I assume STJ would work fine with this. Any particular reason why you say this?

FriteOP•7d ago

i'm using positive numbers

SG97•7d ago

just change it to uint, don't think it's a problem

FriteOP•7d ago

should i get back to Newtonsoft ?

FusedQyou•7d ago

Again, I don't see why it would not work. The only issue seemingly needing a fix is the fact fields are not by default used So either switch to properties, or use the option I shared above

FriteOP•7d ago

'The JSON value could not be converted to System.UInt32. Path: $.layers[0].entities[0]._eid | LineNumber: 21 | BytePositionInLine: 28.' :( where line 21 : "_eid": "74122737",

FusedQyou•7d ago

That's because it's a string, not an integer I assume by default Newtonsoft parses it The correct fix is to pass a proper number Alternatively, add the following to the list of options:

var options = new JsonSerializerOptions()
{
     NumberHandling = JsonNumberHandling.AllowReadingFromString | JsonNumberHandling.WriteAsString
};

var options = new JsonSerializerOptions()
{
     NumberHandling = JsonNumberHandling.AllowReadingFromString | JsonNumberHandling.WriteAsString
};

FriteOP•7d ago

oh thanks i didn't noticed that was a string ok this works! and runs much faster than Newtonsoft thanks guys now lets get into polymorphism

MODiX•7d ago

If you have no further questions, please use /close to mark the forum thread as answered

Pobiega•7d ago

polymorphism in STJ is actually really nice and easy, as long as your variants are known at compile time, and you have some measure of control over the json, or it alread being wellformed (like having a discriminator value) https://learn.microsoft.com/en-us/dotnet/standard/serialization/system-text-json/polymorphism has all the info you need

FriteOP•6d ago

it all works perfectly, thanks! i'm done with json

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✅ Opening a Json file

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