C#_WinForms_CreateGraphics

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

namespace ParentWindow
{
    public partial class Paint : Form
    {
        bool paint = false;
        SolidBrush color;
        public Paint()
        {
            InitializeComponent();
        }

        private void Paint_Load(object sender, EventArgs e)
        {
        }

        private void panel1_MouseUp(object sender, MouseEventArgs e)
        {
            paint = false;
        }

        private void panel1_MouseDown(object sender, MouseEventArgs e)
        {
            paint = true;
        }

        private void panel1_MouseMove(object sender, MouseEventArgs e)
        {
            if (paint)
            {
                color = new SolidBrush(Color.Black);
                Graphics g = panel1.CreateGraphics();
                g.FillEllipse(color, e.X, e.Y, 10, 10);
                g.Dispose();
            }
        }

        private void button1_Click(object sender, EventArgs e)
        {
            Graphics gl = panel1.CreateGraphics();
            gl.Clear(panel1.BackColor);
        }

        private void panel1_Paint(object sender, PaintEventArgs e)
        {

        }

    }
  }