Serialization

Serialization is the process of persisting the state of an object to a file or memory buffer. The persisted data contains all the necessary information you need to reconstruct (deserialize) the state of the object.

Serializable marks a class serializable.

[Serializable]
public class UserPrefs
{
  public string WindowColor;
  public int FontSize;
}

Example using BinaryFormatter to write a Serializable object to a file stream.

UserPrefs userData = new UserPrefs { WindowColor = "Blue", FontSize = 24 };
BinaryFormatter bf = new BinaryFormatter();
using (Stream fs = new File.OpenWrite("user.dat"))
{
  bf.Serialize(fs, userData); 
}

Object Graphs

The CLR accounts for all related objects as well to ensure that the data is persisted correctly. It does this by building an object graph.

(3:Car) -> (2:Radio)
(1:SpecialCar) -> (3:Car)
(1:SpecialCar) -> (2:Radio)

This is one way of representing a graph with three nodes, where: "Car" depends on "Radio", and "SpecialCar" depends on both "Car" and "Radio".

The CLR may represent this as such (specifics not certain from source material):

[Car 3, ref 2], [Radio 2], [SpecialCar 1, ref 3, ref 2]