C# Drag and Drop OXO

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace WindowsFormsApplication2
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            //PictureBox MyX = new PictureBox();
            //PictureBox MyY = new PictureBox();
            InitializeComponent();
                
                MyX.MouseDown +=new MouseEventHandler(MyX_MouseDown);
                MyX.MouseMove +=new MouseEventHandler(MyX_MouseMove);    

                Point pX = new Point(230, 316);
                Point pY = new Point(20, 316);
                Bitmap X = new Bitmap("X.png");
                Bitmap Y = new Bitmap("O.jpg");
                MyX.BackgroundImage = X;
                MyX.BackgroundImageLayout = ImageLayout.Stretch;
                MyY.BackgroundImage = Y;
                MyY.BackgroundImageLayout = ImageLayout.Stretch;
                
                //
                int kolommen = 4;
                int rijen = 4;
                int aantalElementen = (kolommen * rijen) + 1;
                PictureBox[] Boxes = new PictureBox[aantalElementen];
                int tellerIndex = 1;
                for (int tellerRij = 1; tellerRij <= rijen; tellerRij++)
                {
                    for (int tellerKol = 1; tellerKol <= kolommen; tellerKol++)
                    {
                        Boxes[tellerIndex] = new PictureBox();
                        Boxes[tellerIndex].Name = "Picturebox" + tellerIndex.ToString();
                        Point positie = new Point((-50 + (tellerKol * 70)), (-50 + (tellerRij * 70)));
                        Boxes[tellerIndex].Width = 60;
                        Boxes[tellerIndex].BorderStyle = BorderStyle.FixedSingle;
                        Boxes[tellerIndex].Height = 60;
                        Boxes[tellerIndex].Location = positie;
                        Boxes[tellerIndex].AllowDrop = true;
                        tellerIndex++;
                    }
                }
                
                MyX.BorderStyle = BorderStyle.Fixed3D;
                MyX.Height = 60;
                MyX.Width = 60;
                MyX.Image = X;
                MyX.SizeMode = PictureBoxSizeMode.StretchImage;
                MyY.BorderStyle = BorderStyle.Fixed3D;
                MyY.Height = 60;
                MyY.Width = 60;
                MyY.Image = Y;
                MyY.SizeMode = PictureBoxSizeMode.StretchImage;
                MyX.Location = pX;
                MyY.Location = pY;


                this.Controls.AddRange(Boxes);
                this.Controls.Add(MyX);
                this.Controls.Add(MyY);
        }
        bool isDragging = false;
        int CurrentX, CurrentY;

        private void MyX_MouseMove(object sender, MouseEventArgs e)
        {
            if (isDragging == true)
            {
                MyX.Top = MyX.Top + (e.Y - CurrentY);
                MyX.Left = MyX.Left + (e.X - CurrentX);
            }
            
        }

        private void MyX_MouseDown(object sender, MouseEventArgs e)
        {
            isDragging = true;
            CurrentX = e.X;
            CurrentY = e.Y;
            
        }
        
    }
}