// 按下滑鼠
private void Form1_MouseDown(object sender, MouseEventArgs e)
{
Piece piece = board.PlacePiece(e.X, e.Y, nextType);
if (piece != null)
{
this.Controls.Add(piece);
if (nextType == PieceType.Black)
{
nextType = PieceType.White;
}
else if (nextType == PieceType.White)
{
nextType = PieceType.Black;
}
}
}