C#•17mo ago

Newtonsoft.Json Serialization Exception

Trying to deserialize a List<Highscore> for my project and it throws this exception: Unhandled exception. Newtonsoft.Json.JsonSerializationException: Error converting value "{"Name":"Willy","Time":316}" to type 'ReactionGame.Highscore' Code (T is List<Highscore>):

    public virtual async Task<T> Get<T>(string url) where T : class
    {
        using var client = new HttpClient();

        var stringResult = await client.GetStringAsync(url);
        return JsonConvert.DeserializeObject<T>(stringResult, new JsonSerializerSettings{NullValueHandling = NullValueHandling.Ignore});
    }

    public virtual async Task<T> Get<T>(string url) where T : class
    {
        using var client = new HttpClient();

        var stringResult = await client.GetStringAsync(url);
        return JsonConvert.DeserializeObject<T>(stringResult, new JsonSerializerSettings{NullValueHandling = NullValueHandling.Ignore});
    }

Model:

namespace ReactionGame
{
    public class Highscore
    {
        [JsonProperty]
        public string Name { get; set; }
        [JsonProperty]
        public long Time { get; set; }

        public override string ToString()
        {
            return Name + "  -  " + Time;
        }

        [JsonConstructor]
        public Highscore(string name, long time)
        {
            Name = name;
            Time = time;
        }
    }
}

namespace ReactionGame
{
    public class Highscore
    {
        [JsonProperty]
        public string Name { get; set; }
        [JsonProperty]
        public long Time { get; set; }

        public override string ToString()
        {
            return Name + "  -  " + Time;
        }

        [JsonConstructor]
        public Highscore(string name, long time)
        {
            Name = name;
            Time = time;
        }
    }
}

Anyone know what might be wrong? I'm at a loss.

26 Replies

MODiX•17mo ago

Ero#1111

REPL Result: Success

using Newtonsoft.Json;

var json = """
{
  "Name": "Willy",
  "Time": 316
}
""";

var hs = JsonConvert.DeserializeObject<Highscore>(json, new JsonSerializerSettings
{
  NullValueHandling = NullValueHandling.Ignore
});

Console.WriteLine(hs);

class Highscore
{
[JsonProperty]
public string Name { get; set; }
[JsonProperty]
public long Time { get; set; }

public override string ToString()
{
  return Name + "  -  " + Time;
}

[JsonConstructor]
public Highscore(string name, long time)
{
  Name = name;
  Time = time;
}
}

using Newtonsoft.Json;

var json = """
{
  "Name": "Willy",
  "Time": 316
}
""";

var hs = JsonConvert.DeserializeObject<Highscore>(json, new JsonSerializerSettings
{
  NullValueHandling = NullValueHandling.Ignore
});

Console.WriteLine(hs);

class Highscore
{
[JsonProperty]
public string Name { get; set; }
[JsonProperty]
public long Time { get; set; }

public override string ToString()
{
  return Name + "  -  " + Time;
}

[JsonConstructor]
public Highscore(string name, long time)
{
  Name = name;
  Time = time;
}
}

Console Output

Willy  -  316

Willy  -  316

Compile: 692.423ms | Execution: 158.707ms | React with ❌ to remove this embed.

ero•17mo ago

¯\_(ツ)_/¯

𝕭𝖔𝖙𝖙𝖑𝖊_𝕭𝖆𝖗𝖔𝖓•17mo ago

Thanks xD What did you change exactly?

ero•17mo ago

Nothing Just showing your that it should work

𝕭𝖔𝖙𝖙𝖑𝖊_𝕭𝖆𝖗𝖔𝖓•17mo ago

Bruh 😓 thanks anyways :)

MODiX•17mo ago

Check your private messages, @𝕭𝖔𝖙𝖙𝖑𝖊_𝕭𝖆𝖗𝖔𝖓.

MODiX•17mo ago

Ero#1111

REPL Result: Success

using Newtonsoft.Json;

var json = """
[
{
  "Name": "Willy",
  "Time": 316
},
{
  "Name": "Willy",
  "Time": 316
}
]
""";

var hs = JsonConvert.DeserializeObject<List<Highscore>>(json, new JsonSerializerSettings
{
  NullValueHandling = NullValueHandling.Ignore
});

Console.WriteLine(hs[0]);

class Highscore
{
[JsonProperty]
public string Name { get; set; }
[JsonProperty]
public long Time { get; set; }

public override string ToString()
{
  return Name + "  -  " + Time;
}

[JsonConstructor]
public Highscore(string name, long time)
{
  Name = name;
  Time = time;
}
}

using Newtonsoft.Json;

var json = """
[
{
  "Name": "Willy",
  "Time": 316
},
{
  "Name": "Willy",
  "Time": 316
}
]
""";

var hs = JsonConvert.DeserializeObject<List<Highscore>>(json, new JsonSerializerSettings
{
  NullValueHandling = NullValueHandling.Ignore
});

Console.WriteLine(hs[0]);

class Highscore
{
[JsonProperty]
public string Name { get; set; }
[JsonProperty]
public long Time { get; set; }

public override string ToString()
{
  return Name + "  -  " + Time;
}

[JsonConstructor]
public Highscore(string name, long time)
{
  Name = name;
  Time = time;
}
}

Console Output

Willy  -  316

Willy  -  316

Compile: 742.622ms | Execution: 179.356ms | React with ❌ to remove this embed.

ero•17mo ago

Still works for a list too

𝕭𝖔𝖙𝖙𝖑𝖊_𝕭𝖆𝖗𝖔𝖓•17mo ago

Hm Might have found it Seems the json string has been altered somehow

["{\"Name\":\"Pet\",\"Time\":316}","{\"Name\":\"Pet\",\"Time\":278}"]

["{\"Name\":\"Pet\",\"Time\":316}","{\"Name\":\"Pet\",\"Time\":278}"]

ero•17mo ago

where are you getting this input?

𝕭𝖔𝖙𝖙𝖑𝖊_𝕭𝖆𝖗𝖔𝖓•17mo ago

Im sending the data from my game to a web api then using the get method to retrieve it from the site

ero•17mo ago

is the web api strictly a middleman for this or does it do more?

𝕭𝖔𝖙𝖙𝖑𝖊_𝕭𝖆𝖗𝖔𝖓•17mo ago

No it is just supposed to store data

ero•17mo ago

then why not just send the data from the game directly to the app?

𝕭𝖔𝖙𝖙𝖑𝖊_𝕭𝖆𝖗𝖔𝖓•17mo ago

That is what i am attempting using the post and get endpoints

ero•17mo ago

well no, that's a middleman

𝕭𝖔𝖙𝖙𝖑𝖊_𝕭𝖆𝖗𝖔𝖓•17mo ago

this is what the repo looks like roughly

𝕭𝖔𝖙𝖙𝖑𝖊_𝕭𝖆𝖗𝖔𝖓•17mo ago

The WebApi parts job is to take the data sent from the reactiongame and store it into a SQLite database The get method should then get that data and return it to the game

ero•17mo ago

right well, anyway. that seems like incorrectly formatted json there shouldn't be quotes after [ and before ]

𝕭𝖔𝖙𝖙𝖑𝖊_𝕭𝖆𝖗𝖔𝖓•17mo ago

ait then i will look into this :)

Pobiega•17mo ago

that looks like a List<string> where each string is a json serialized object

ero•17mo ago

yup also consider using System.Text.Json instead of Newtonsoft

𝕭𝖔𝖙𝖙𝖑𝖊_𝕭𝖆𝖗𝖔𝖓•17mo ago

Yeah I'll try that Thanks ^^

ero•17mo ago

it won't fix this! but it is still just. better in every way

MODiX•17mo ago

Ero#1111

REPL Result: Success

using System.Text.Json;

var json = """
[
  {
    "Name": "Pet",
    "Time": 316
  },
  {
    "Name": "Pet",
    "Time": 278
  }
]
""";

var hs = JsonSerializer.Deserialize<List<Highscore>>(json);
Console.WriteLine(hs[0]);

record Highscore(
string Name,
int Time);

using System.Text.Json;

var json = """
[
  {
    "Name": "Pet",
    "Time": 316
  },
  {
    "Name": "Pet",
    "Time": 278
  }
]
""";

var hs = JsonSerializer.Deserialize<List<Highscore>>(json);
Console.WriteLine(hs[0]);

record Highscore(
string Name,
int Time);

Console Output

Highscore { Name = Pet, Time = 316 }

Highscore { Name = Pet, Time = 316 }

Compile: 753.600ms | Execution: 95.491ms | React with ❌ to remove this embed.

𝕭𝖔𝖙𝖙𝖑𝖊_𝕭𝖆𝖗𝖔𝖓•17mo ago

Yup

Gaming

Programming

Newtonsoft.Json Serialization Exception