JSonNet boolean serialization

Question

Quick question:

In JSONNet - how do i get bool true/false to serialize as bool 1/0

I can see how we handle null values and all that just cant seem to find how to do this.

is this possible?

Answer 1

You can implement a custom converter like this:

[TestFixture]
public class CustomJsonSerialization
{
    [Test]
    public void Test()
    {
        string serializeObject = JsonConvert.SerializeObject(true, new BoolConverter());
        Assert.That(serializeObject, Is.EqualTo("1"));
        var deserializeObject = JsonConvert.DeserializeObject<bool>(serializeObject, new BoolConverter());
        Assert.That(deserializeObject, Is.True);
    }
}

public class BoolConverter : JsonConverter
{
    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
    {
        writer.WriteValue(((bool)value) ? 1 : 0);
    }

    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
    {
        return reader.Value.ToString() == "1";
    }

    public override bool CanConvert(Type objectType)
    {
        return objectType == typeof(bool);
    }
}

Answer 2

Inspired by this response in similar question it can be solved like the following.

[JsonIgnore]
public bool SomeFlag { get; set; }

[JsonProperty(nameof(SomeFlag))]
public int SomeFlagAsInt
{
    get => SomeFlag ? 1 : 0;
    set => SomeFlag = value > 0;
}

Answer 3

@DavidPeden answer v2

Better string handling

/// <summary>
///  CUSTOM BOOLEAN -> 0 | 1 CONVERTER
/// </summary>
public class BoolConverter : JsonConverter
{
    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
    {
        writer.WriteValue(bool.TryParse(value?.ToString(), out var parsed) ? (parsed ? 1 : 0) : 0);
    }

    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
    {
        return int.TryParse(reader.Value?.ToString(), out var parsed) && parsed == 1;
    }

    public override bool CanConvert(Type objectType)
    {
        return objectType == typeof(bool) || objectType == typeof(bool?);
    }
}

Answer 4

Here's my version (in vb) if anyone needs it. It also handles nullable Boolean

Imports Newtonsoft.Json

Public Class MyBooleanConverter
    Inherits JsonConverter

Public Overrides ReadOnly Property CanWrite As Boolean
    Get
        Return True
    End Get
End Property

Public Overrides Sub WriteJson(writer As JsonWriter, value As Object, serializer As JsonSerializer)
    Dim boolVal As Boolean = value
    writer.WriteValue(If(boolVal, 1, 0))
End Sub

Public Overrides Function ReadJson(reader As JsonReader, objectType As Type, existingValue As Object, serializer As JsonSerializer) As Object
    Dim value = reader.Value
    If IsNothing(value) OrElse String.IsNullOrWhiteSpace(value.ToString()) OrElse "0" = value Then
        Return False
    End If
    If 0 = String.Compare("yes", value, True) OrElse 0 = String.Compare("true", value, True) Then
        Return True
    End If
    Return False
End Function

Public Overrides Function CanConvert(objectType As Type) As Boolean
    Return objectType = GetType(Boolean) OrElse objectType = GetType(Boolean?) 'OrElse objectType = GetType(String)
End Function
End Class

I started this based on @John here: how to get newtonsoft to deserialize yes and no to boolean

Answer 5

Declare two separate properties, hide the real one from serialization, and use the "fake" int one instead. Decorate both with Newton's attributes like this:

[JsonIgnore] public bool Bool { internal get; set; }
[JsonProperty("your_dispay_name")] public string Int { get { return this.Bool ? 1 : 0; } }