问将值从类传递到不同的窗体上显示&以编程方式单击事件处理？

EN

namespace Chess
{
    public class GridSquare : PictureBox
    {
        private int x;
        private int y;

        private ChessPiece piece;

        public int X { get { return x; } }
        public int Y { get { return y; } }

        public ChessPiece Piece 
        {
            get { return piece; }
            set 
            {
                piece = value;
                if (value == null)
                    this.BackgroundImage = null;
                else
                    this.BackgroundImage = piece.GetImage();
            }
        }

        public GridSquare(int x, int y)
        {
            int ButtonWidth = 64;
            int ButtonHeight = 64;
            int Distance = 20;
            int start_x = 10;
            int start_y = 10;

            this.x = x;
            this.y = y;

            this.Top = start_x + (x * ButtonHeight + Distance + x);
            this.Left = start_y + (y * ButtonWidth + Distance + y);
            this.Width = ButtonWidth;
            this.Height = ButtonHeight;
            this.Text = "X: " + x.ToString() + " Y: " + y.ToString();

            this.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle;

            this.Click += new System.EventHandler(gridSquare_Click);
        }

        private void gridSquare_Click(object sender, EventArgs e)
        {
            GridSquare gs = (GridSquare)sender;
            if (gs.Piece != null)
                {
                    //Change: need to show xy of sqaure clicked on a label or textbox on the main window.
                MessageBox.Show("You clicked a " + gs.Piece.GetName() + " at (" + gs.X + ", " + gs.Y + ")");

                //Change: need to click for change in colour, then second click to revert back
                this.BackColor = Color.LightBlue;
                } 
            else
                {
                    //Change: need to show xy of clicked square but including meesage stating the sqaure needs to be occupied by a piece.
                    MessageBox.Show("You clicked (" + gs.X + ", " + gs.Y + ")");
                }
        }
    }
}