Unexpected Serialization implementing System.Text.Json in .NET 7 for Interface Properties
Quick question that's been bugging me - I'm stuck on something that should probably be simple. I've been struggling with this for a few days now and could really use some help. I am working with an scenario when trying to serialize a class that contains properties defined as interfaces using `System.Text.Json`. The properties are not being serialized correctly, and I am getting a `JsonException` that states the property want to be converted to the expected type. Here’s a simplified version of my code: ```csharp public interface IMyInterface { string Name { get; set; } } public class MyClass { public IMyInterface MyProperty { get; set; } } public class MyInterfaceImplementation : IMyInterface { public string Name { get; set; } } var myObject = new MyClass { MyProperty = new MyInterfaceImplementation { Name = "Test" } }; var options = new JsonSerializerOptions { WriteIndented = true }; var json = JsonSerializer.Serialize(myObject, options); ``` When I run this code, I receive the following behavior: ``` System.Text.Json.JsonException: The JSON value could not be converted to MyNamespace.IMyInterface. Path: $.MyProperty | Line: 1 | Position: 19. ``` I have tried various approaches like using `[JsonConverter(typeof(JsonStringEnumConverter))]` and creating a custom converter for the interface, but nothing seems to work. Here’s an example of a custom converter I attempted: ```csharp public class MyInterfaceConverter : JsonConverter<IMyInterface> { public override IMyInterface Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options) { // Implementation for deserialization } public override void Write(Utf8JsonWriter writer, IMyInterface value, JsonSerializerOptions options) { writer.WriteStartObject(); writer.WriteString("Name", value.Name); writer.WriteEndObject(); } } ``` However, I am not sure how to register this converter correctly or if there are any additional steps needed to make it fully functional. Can anyone guide me on how to properly serialize properties of interface types in .NET 7 using `System.Text.Json`? Any help would be greatly appreciated! This is part of a larger API I'm building. What am I doing wrong?