Deep copy of objects in C#

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Introduction

Below you can find a short article on how to do a deep copy of objects using Reflection in C#. Please be aware that this is my first article here (even first article in the English language...)

Background

The class (called HCloner) has a DeepCopy function. It drills down the entire object fields structure (using System.Reflection) and copies it into a new location that is returned after that.

Members that are copied are fields - no need to copy properties since behind every property, there is a field. A property itself cannot hold any value.

Using the code

Let's look at the "core" code:

using System;
using System.Reflection;

namespace HAKGERSoft {

    public class HCloner {

        public static T DeepCopy<T>(T obj) {
            if(obj==null)
                throw new ArgumentNullException("Object cannot be null");
            return (T)Process(obj);
        }

        static object Process(object obj) {
            if(obj==null)
                return null;
            Type type=obj.GetType();
            if(type.IsValueType || type==typeof(string)) {
                return obj;
            }
            else if(type.IsArray) {
                Type elementType=Type.GetType(
                     type.FullName.Replace("[]",string.Empty));
                var array=obj as Array;
                Array copied=Array.CreateInstance(elementType,array.Length);
                for(int i=0; i<array.Length; i++) {
                    copied.SetValue(Process(array.GetValue(i)),i);
                }
                return Convert.ChangeType(copied,obj.GetType());
            }
            else if(type.IsClass) {
                object toret=Activator.CreateInstance(obj.GetType());
                FieldInfo[] fields=type.GetFields(BindingFlags.Public| 
                            BindingFlags.NonPublic|BindingFlags.Instance);
                foreach(FieldInfo field in fields) {
                    object fieldValue=field.GetValue(obj);
                    if(fieldValue==null)
                        continue;
                    field.SetValue(toret,Process(fieldValue));
                }
                return toret;
            }
            else
                throw new ArgumentException("Unknown type");
        }

    }
}

Using it is very simple - just call the DeepCopy function.

History

This is a very alpha-pre version of my function. I'm looking forward for some feedback from you - any issues found will be analysed and fixed (at least, I'll try).