/// <summary>Returns a list of legal moves from all pieces this turn.</summary>
        /// <param name="optionalJumping">Overrides the game's OptionalJumping parameter for the enumeration.</param>
        /// <returns>A list of legal moves.</returns>
        public CheckersMove[] EnumLegalMoves(bool optionalJumping)
        {
            if ((!isPlaying) && (winner == 0))
            {
                throw new InvalidOperationException("Operation requires game to be playing.");
            }
            Stack     incompleteMoves = new Stack();
            ArrayList moves           = new ArrayList();

            foreach (CheckersPiece piece in EnumMovablePieces(optionalJumping))
            {
                incompleteMoves.Push(BeginMove(piece));
            }
            while (incompleteMoves.Count > 0)
            {
                CheckersMove move = (CheckersMove)incompleteMoves.Pop();
                foreach (Point location in move.EnumMoves(optionalJumping))
                {
                    CheckersMove nextMove = move.Clone();
                    if (!nextMove.Move(location))
                    {
                        continue;
                    }
                    if (nextMove.CanMove)
                    {
                        incompleteMoves.Push(nextMove);
                    }
                    if (!nextMove.MustMove)
                    {
                        moves.Add(nextMove);
                    }
                }
            }
            return((CheckersMove[])moves.ToArray(typeof(CheckersMove)));
        }