How can i change background color of Windows form?

Compiler gives error to pen1 = new System.Drawing.Color(cd.Color, 2F);
and mentioned does not take constructor that takes 2 arguments .Please check it.

You just need to change one line:

Thank you very Much,by the way how can  I use this kind of method to change the color of shapes after draw.In below, My code just draw the shapes with blue how can i use your code in this question?

My code:

 private System.Drawing.Graphics g;
 private System.Drawing.Pen pen1 = new System.Drawing.Pen(Color.Blue, 2F);


 private void butEllipse_Click(object sender, EventArgs e)
        {
            g = PictureBox1.CreateGraphics();
            g.DrawEllipse(pen1, 50, 50, 100, 150);
        }

 private void butRectangle_Click(object sender, EventArgs e)
        {
            g = PictureBox1.CreateGraphics();
            g.DrawRectangle(pen1, 30, 30, 50, 60);
        }

That's right.

The colors are all shown in little boxes.

The user just has to select one and click OK.

Another way to change colors is to use a ColorDialog control.

This has the advantage that the user can actually see what the colors look like. However, you're limited to a choice of 48 colors though another 16 'custom' colors can be added if you wish.

Here's how you'd show a ColorDialog on, say, a button click:

Thank you Very much sir.

You can choose from all 140 'named' colors (from AliceBlue to YellowGreen) supported by WF by changing the code in Form_Load to the following:

} 

Try this: