C#

using System;
using System.IO;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Formatters.Binary;
 
[Serializable()]
public class MyClass {
 
	public MyClass(string name) {
 		_Name = name;
	}
 
	public string Name {
		get { return _Name; }
	}
 
	private string _Name;
 
}
 
[Serializable()]
class MyClassCollection {
 
	public MyClassCollection() {
		_Items = new MyClass[4];
	}
 
	public MyClass this[int index] {
		get { return _Items[index]; }
		set { _Items[index] = value; }
	}
 
	public override string ToString() {
		string result = "MyClassCollection {";
		for (int i = 0; i < _Items.Length; i++)
			result += (i != 0 ? ", " : "") + (_Items[i] != null ? _Items[i].Name : "[null]");
		result += "}";
		return result;
	}
 
	private MyClass[] _Items;
 
	[STAThread]
	static void Main(string[] args) {
		BinaryFormatter formatter = new BinaryFormatter();
		MemoryStream stream = new MemoryStream();
		// Populate collection
		MyClassCollection col = new MyClassCollection();
		col[0] = new MyClass("Item #1");
		col[2] = new MyClass("Item #2");
		Console.WriteLine(col);
		// Serialize collection and reset stream to beginning
		formatter.Serialize(stream, col);
		col = null;
		stream.Seek(0, SeekOrigin.Begin);
		// Deserialize collection
		col = (MyClassCollection)formatter.Deserialize(stream);
		stream.Close();
		Console.WriteLine(col);
		Console.Read();
	}
 
}

MyClassCollection {Item #1, [null], Item #2, [null]}
MyClassCollection {Item #1, [null], Item #2, [null]}