DrawTest2

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Threading;
using System.Windows.Forms;

namespace WindowsFormsApplication2
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private bool move = false;
        private Point location = new Point(0, 0);
        private Point init = new Point(0, 0);

        private void Form1_Paint(object sender, PaintEventArgs e)
        {
            MessageBox.Show("A");

            if(move)
            {
                Graphics g = e.Graphics;
                Pen p = new Pen(Color.Black, 5f);

                g.DrawRectangle(p, new Rectangle(init, new Size(50, 50)));

                while(location.X != init.X && location.Y != init.Y)
                {
                    if(location.X < init.X)
                    {
                        init.X--;
                    }
                    else if (location.X > init.X)
                    {
                        init.X++;
                    }

                    if(location.Y < init.Y)
                    {
                        init.Y--;
                    }
                    else if (location.Y > init.Y)
                    {
                        init.Y++;
                    }

                    Thread.Sleep(500);
                }

                g.Dispose();
                p.Dispose();
            }
        }

        private void panel1_Click(object sender, EventArgs e)
        {
            if(!move)
            {
                move = true;
                Refresh();
            }
            else
            {
                move = false;
            }
        }

        private void panel1_MouseMove(object sender, MouseEventArgs e)
        {
            init = e.Location;
        }
    }
}