I need to implement C# deep copy constructors with inheritance. What patterns are there to choose from?

Question

I wish to implement a deepcopy of my classes hierarchy in C#

public Class ParentObj : ICloneable
{
    protected int   myA;
    public virtual Object Clone          


        

Answer 1

The best way is by serializing your object, then returning the deserialized copy. It will pick up everything about your object, except those marked as non-serializable, and makes inheriting serialization easy.

[Serializable]
public class ParentObj: ICloneable
{
    private int myA;
    [NonSerialized]
    private object somethingInternal;

    public virtual object Clone()
    {
        MemoryStream ms = new MemoryStream();
        BinaryFormatter formatter = new BinaryFormatter();
        formatter.Serialize(ms, this);
        object clone = formatter.Deserialize(ms);
        return clone;
    }
}

[Serializable]
public class ChildObj: ParentObj
{
    private int myB;

    // No need to override clone, as it will still serialize the current object, including the new myB field
}

It is not the most performant thing, but neither is the alternative: relection. The benefit of this option is that it seamlessly inherits.