JOS.SystemTextJsonDictionaryStringObjectJsonConverter

https://josef.codes/custom-dictionary-string-object-jsonconverter-for-system-text-json/

Information

System.Text.Json custom JsonConverter that allows you to deserialize to a Dictionary<string, object>.

Note It supports serialization as well, but I recommend you to only use this custom JsonConverter for Deserialization. If you use it for serialization as well, it will be a bit slower than the default behaviour of System.Text.Json because of how custom JsonConverters work. Basically, to avoid an infinite loop I need to cast the value to IDictionary<string, object?> before serializing. If not, System.Text.Json will call my JsonConverter again, and again, and again...until it crashes with a stack overflow, more info here.

It's really easy to avoid though. When serializing, don't pass in any options that contains this JsonConverter in it's converter list. If you do, it will still work, just a bit slower because of the cast.

Install

Just the JsonConverter

dotnet add package JOS.SystemTextJson.DictionaryStringObject.JsonConverter

JsonConverter + Model binder for ASP.Net Core

dotnet add package JOS.SystemTextJson.DictionaryStringObject.JsonConverter.AspNetCore

Tests

This runs all tests except the tests in Deserialization_DefaultTests. The tests in that class are supposed to fail. They test if the default behaviour of System.Text.Json correctly handles deserialization to Dictionary<string, object>. When they don't fail anymore, this package is not needed... :)

dotnet test --filter 'FullyQualifiedName!~Deserialization_DefaultTests'