Json.NET now detects types that have the SerializableAttribute and serializes all the fields on that type, both public and private, and ignores the properties. This is useful when you’re interested in round-tripping the data on a type and don’t care what the JSON looks like.
If you are serializing types that have the attribute and don’t want the new behaviour, it can either be overridden on a type using the JsonObjectAttribute or disabled globally by setting IgnoreSerializableAttribute on DefaultContractResolver to true.
Update: IgnoreSerializableAttribute is true by default in release 3. If you want it you can still achieve this effect by either setting IgnoreSerializableAttribute to false or adding [JsonObject(MemberSerialization.Fields)] to your class.
- New feature - Added support for the SerializableAttribute and serializing a type's internal fields
- New feature - Added MaxDepth to JsonReader/JsonSerializer/JsonSerializerSettings
- New feature - Added support for ignoring properties with the NonSerializableAttribute
- Fix - Fixed deserializing a null string throwing a NullReferenceException
- Fix - Fixed JsonTextReader incorrectly reading from a slow stream
- Fix - Fixed CultureInfo not being overridden on JsonSerializerProxy
- Fix - Fixed full trust security check in .NET 2.0 & .NET 3.5
- Fix - Fixed XmlNodeConverter not turning all attribute properties into attributes
- Fix - Fixed comparing JObjects to ignore property order
- Fix - Fixed reading invalid Unicode surrogate pairs
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Json.NET 4.5 Release 2 Download – Json.NET source code, documentation and binaries