# ReferenceCodec.MarkValueField(SerializerSession)

[Type overview](/orleans/docs/api/csharp/microsoft.orleans.serialization/orleans.serialization.codecs.referencecodec/) | [Methods](/orleans/docs/api/csharp/microsoft.orleans.serialization/orleans.serialization.codecs.referencecodec/methods/)

[Source](https://github.com/dotnet/orleans/blob/e4e752cedecc2976811db49802c7a999b1f1c704/src/Orleans.Serialization/Codecs/ReferenceCodec.cs#L21)

```csharp
public static void MarkValueField(SerializerSession session)
```

Indicates that the field being serialized or deserialized is a value type.

### Parameters

- `session` (`SerializerSession`): The serializer session.