How to have System.Text.Json skip properties of types that are not serializable?

[WenningQiu]

I am running into an exception when serializing objects with a property of type Func<string>. Since Func<string> is code, it does not make any sense for it to be serialized at all.

        public Func<string> MsoCalculator
        {
            get => _msoCalculator ?? GlobalMsoCalculator;
            set => _msoCalculator = value;
        }

I was expecting such properties to be automatically excluded by System.Text.Json.JsonSerializer, but apparently System.Text.Json.JsonSerializer pressed ahead and ran into an exception:

System.NotSupportedException : Serialization and deserialization of 'System.Func`1[[System.String, System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]]' instances is not supported. The unsupported member type is located on type 'System.Func`1[System.String]'. Path: $.DiagnosticsContext.Mso.MsoCalculator.
  ----> System.NotSupportedException : Serialization and deserialization of 'System.Func`1[[System.String, System.Private.CoreLib, Version=6.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]]' instances is not supported.
   at System.Text.Json.ThrowHelper.ThrowNotSupportedException(WriteStack& state, NotSupportedException ex)
   at System.Text.Json.Serialization.JsonConverter`1.WriteCore(Utf8JsonWriter writer, T& value, JsonSerializerOptions options, WriteStack& state)
   at System.Text.Json.Serialization.Metadata.JsonTypeInfo`1.Serialize(Utf8JsonWriter writer, T& rootValue, Object rootValueBoxed)
   at System.Text.Json.Serialization.Metadata.JsonTypeInfo`1.SerializeAsObject(Utf8JsonWriter writer, Object rootValue)
   at System.Text.Json.JsonSerializer.WriteStringAsObject(Object value, JsonTypeInfo jsonTypeInfo)

So my questions:

1. Should System.Text.Json.JsonSerializer be designed to skip properties of types that are not serializable?
2. Since System.Text.Json.JsonSerializer currently does not skip such properties, what is the best way to customize System.Text.Json.JsonSerializer to do that? (I know slapping [JsonIgnore] attribute on the property will help, but I don't want to do it manually on individual properties.

[eiriktsarpalis]

JsonIgnore is the recommended way to do this. You can also remove properties programmatically by manipulating the JsonTypeInfo.Properties property via the contract customization APIs.