Konami Code in C#

Question

I am looking to have a C# application implement the Konami Code to display an Easter Egg. http://en.wikipedia.org/wiki/Konami_Code

What is the best way to do this?<

Answer 1

Here is another implementation, based on James answer and comments:

using System.Windows.Forms;

namespace WindowsFormsApplication1
{
    public class KonamiSequence
    {
        private readonly Keys[] _code = { Keys.Up, Keys.Up, Keys.Down, Keys.Down, Keys.Left, Keys.Right, Keys.Left, Keys.Right, Keys.B, Keys.A };
        private int _index = 0;

        public bool IsCompletedBy(Keys key)
        {
            if (key == _code[_index]) {
                if (_index == _code.Length - 1) {
                    _index = 0;
                    return true;
                }
                ++_index;
            } else {
                _index = 0;
            }

            return false;
        }
    }
}

• Doesn't bother caching _code.Length (see this article), however note it's accessed only when a key from the sequence is typed.
• Accepts the case "UUUUUUUUUUDDLRLRBA".
• Of course, resets the sequence if a wrong key is typed.