how to draw something on a panel by clicking a button - c#-3.0

Question

i have a panel and a button. i.e:
private void button1_Click(object sender, EventArgs e)
{
panel2.Paint += new PaintEventHandler(panel2_Paint);
panel2.Refresh();
}
and:
private void panel2_Paint(object sender, PaintEventArgs e)
{
Graphics g = this.CreateGraphics();
Graphics[,] g1 = new Graphics[140, 140];
int[,] graph = new int[140, 140];
int i, j;
for (i = 0; i < 140; i++)
for (j = 0; j < 140; j++)
{
graph[i, 8] = 1;
graph[i, 10] = 1;
}
Pen p = new Pen(Color.Blue);
SolidBrush mySolidColorBrush = new SolidBrush(Color.Blue);
Graphics a;
a = this.CreateGraphics();
for (i = 1; i <= 10; i++)
for (j = 1; j <= 14; j++)
{
g.DrawEllipse(p, 80 * i, 80 * j, 10, 10);
g.FillEllipse(mySolidColorBrush, 80 * i, 80 * j, 20, 20);
a.DrawLine(Pens.Blue, 80 * i, 80 * j, 80 * (i - 1), 80 * (j - 1));
}
}
when i click the button the output should be displayed on panel but in my case it is displayed on form.

Answer 1

You should create your own user control doing the drawing task.
public partial class UserControl1 : UserControl
{
public UserControl1()
{
InitializeComponent();
}
public void DrawStuff()
{
this.Paint += new PaintEventHandler(panel1_Paint);
this.Refresh();
}
private void panel1_Paint(object sender, PaintEventArgs e)
{
Graphics g = e.Graphics;
Graphics[,] g1 = new Graphics[140, 140];
int[,] graph = new int[140, 140];
int i, j;
for (i = 0; i < 140; i++)
for (j = 0; j < 140; j++)
{
graph[i, 8] = 1;
graph[i, 10] = 1;
}
Pen p = new Pen(Color.Blue);
SolidBrush mySolidColorBrush = new SolidBrush(Color.Blue);
Graphics a;
a = this.CreateGraphics();
for (i = 1; i <= 10; i++)
for (j = 1; j <= 14; j++)
{
g.DrawEllipse(p, 80 * i, 80 * j, 10, 10);
g.FillEllipse(mySolidColorBrush, 80 * i, 80 * j, 20, 20);
a.DrawLine(Pens.Blue, 80 * i, 80 * j, 80 * (i - 1), 80 * (j - 1));
}
}
}
Then you can just call the public method draw stuff from your parent control.
private void button1_Click(object sender, EventArgs e)
{
userControl11.DrawStuff();
}