Deep clone an object in .NET

There are two types of object cloning; deep and shallow.

A shallow clone creates a new instance of the same type as the original object, with all its value-typed fields copied. However, the reference type fields still point to the original objects; and so the "new" object and the original reference to the same object. On the other hand, a deep clone of an object contains a full copy of everything directly or indirectly referenced by the object - and so you get a "true" copy.

One of the easiest ways to deep-copy an object is to serialize the object into memory and de-serialize it again - although this does require the object graph to be serializable. Here's a handy code snippet to do this:

public static object CloneObject(object obj)
{
using (MemoryStream memStream = new MemoryStream())
{
BinaryFormatter binaryFormatter = new BinaryFormatter(null,
new StreamingContext(StreamingContextStates.Clone));
binaryFormatter.Serialize(memStream, obj);
memStream.Seek(0, SeekOrigin.Begin);
return binaryFormatter.Deserialize(memStream);
}
}

You could then implement the ICloneable interface on your object like so:

public class MyObject  : ICloneable {
public object Clone()
{
return ObjectUtility.CloneObject(this);
}
...
}

You might also like...

Comments

James Crowley James first started this website when learning Visual Basic back in 1999 whilst studying his GCSEs. The site grew steadily over the years while being run as a hobby - to a regular monthly audience ...

Contribute

Why not write for us? Or you could submit an event or a user group in your area. Alternatively just tell us what you think!

Our tools

We've got automatic conversion tools to convert C# to VB.NET, VB.NET to C#. Also you can compress javascript and compress css and generate sql connection strings.

“The trouble with programmers is that you can never tell what a programmer is doing until it's too late.” - Seymour Cray