gistfile1.txt

class TheClass
{
	public int Val1;
	public int Val2;
	public int Val3;
	public TheClass Old;

	public void Remember()
	{
		Old = new TheClass();
		Old.Val1 = Val1;
		Old.Val2 = Val2;
		Old.Val3 = Val3;
	}
}

internal class Program
{
	private static void Main(string[] args)
	{
		TheClass aClass = new TheClass();

		aClass.Val1 = 5;

		aClass.Remember();

		aClass.Val1 = 10;

		Console.WriteLine(aClass.Old.Val1);

		Console.ReadKey();
	}
}