using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
 
namespace WindowsApplication1
{
    public partial class Form1 : Form
    {
        private int x = 0;
        private int y = 0;
        public Form1()
        {
            InitializeComponent();
        }
 
        private void button1_MouseDown(object sender, MouseEventArgs e)
        {
            x = e.X;
            y = e.Y;
        }
 
        private void button1_MouseMove(object sender, MouseEventArgs e)
        {
            if (e.Button == MouseButtons.Left)
            {
                button1.Left = (button1.Left + e.X) - x;
                button1.Top = (button1.Top +e.Y)-y;
            }
        }
    }
}