System.Text.Json NotSupportedException

Exception message:

System.NotSupportedException: Serialization and deserialization of 'System.IntPtr' instances are not supported. Path: $.Data.Exception.TargetSite.MethodHandle.Value.
       ---> System.NotSupportedException: Serialization and deserialization of 'System.IntPtr' instances are not supported.
         at System.Text.Json.Serialization.Converters.UnsupportedTypeConverter`1.Write(Utf8JsonWriter writer, T value, JsonSerializerOptions options)
         at System.Text.Json.Serialization.JsonConverter`1.TryWrite(Utf8JsonWriter writer, T& value, JsonSerializerOptions options, WriteStack& state)
         at System.Text.Json.Serialization.Metadata.JsonPropertyInfo`1.GetMemberAndWriteJson(Object obj, WriteStack& state, Utf8JsonWriter writer)
         at System.Text.Json.Serialization.Converters.ObjectDefaultConverter`1.OnTryWrite(Utf8JsonWriter writer, T value, JsonSerializerOptions options, WriteStack& state)
         at System.Text.Json.Serialization.JsonConverter`1.TryWrite(Utf8JsonWriter writer, T& value, JsonSerializerOptions options, WriteStack& state

[BrennanConroy]

Feel free to close it if you think it’s not a problem, thanks again.

Yeah, I don’t think this is an issue in the framework code. If you’re curious what’s causing the issue you could try to view the exception being thrown from your API and see what types are on it that aren’t serializer friendly.

[danmoseley]

I am going to move this to ASP.NET. It seems the JSON serializer is working as expected, the caller is SystemTextJsonOutputFormatter.