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Unexpected character encountered while parsing value ASP.NET Core and Newtonsoft


I am trying to parse a JSON file into an object using Newtonsoft in my ASP.NET Core application but I keep getting this error:

Newtonsoft.Json.JsonReaderException: 'Unexpected character encountered while parsing value: {. Path 'palette.swatch', line 7, position 15.'

I've tried using the StreamReader class and now MemoryStream class. I've confirmed validated the JSON online and checked it is UTF-8 too. Both ways I receive the same error. I also manually checked the JSON but I can't see anything that would make it unreadable.

Here's the method that is throwing the exception:

public async Task<int> PostDefinition(IFormFile file)
{
    MemoryStream ms = new MemoryStream();
    file.CopyTo(ms);
    byte[] bytes = ms.ToArray();
    string s = Encoding.UTF8.GetString(bytes);

    Definition definition = Newtonsoft.Json.JsonConvert.DeserializeObject<Definition>(s);
    Definition x = ObjectMapper.Map<Definition>(Definition);

    return await _definitions.InsertAndGetIdAsync(x);
}

This is the segment of the JSON that is throwing an error:

{
  "name": "Definition",
  "id": 2,
  "palette": {
    "name": "Test Palette",
    "default": false,
    "swatch": {
      "colors": {
        "Color 1": "transparent",
        "Color 2": "transparent",
        "Color 3": "transparent",
        "Color 4": "transparent",
        "Color 5": "transparent",
        "Color 6": "transparent",
        "Color 7": "transparent",
        "Color 8": "transparent"
      }
    }
  }
}

What could be causing the exception and what can I try to remedy it? I've tried searching and nothing I try seems to work.


Solution

  • this works for me

     Definition definition = Newtonsoft.Json.JsonConvert.DeserializeObject<Definition>(s);
    

    classes

    public partial class Definition
        {
            [JsonProperty("name")]
            public string Name { get; set; }
    
            [JsonProperty("id")]
            public long Id { get; set; }
    
            [JsonProperty("palette")]
            public Palette Palette { get; set; }
        }
    
        public partial class Palette
        {
            [JsonProperty("name")]
            public string Name { get; set; }
    
            [JsonProperty("default")]
            public bool Default { get; set; }
    
            [JsonProperty("swatch")]
            public Swatch Swatch { get; set; }
        }
    
        public partial class Swatch
        {
            [JsonProperty("colors")]
            public Dictionary<string,string> Colors { get; set; }
        }