How to avoid flickering of graphic object when drawn on picture box in C#?

Question

I am not good at graphic plotting in C#. I am trying to do an animated plotting of a rectangular point on an Image in PictureBox. However, I am facing some flickering issues, I couldn't find the way; how to resolve this issue.

g = pictureBox1.CreateGraphics();
g.FillRectangle(Brushes.Green, Convert.ToInt32(x), Convert.ToInt32(y), 10, 10);

Thread.Sleep(20);
invalidate_pictureBox1();
update_pictureBox1();    

I have studied from other forums that this issue can be resolved using Timer instead of Thread sleep but don't know how to do it.

Answer 1

Draw what you want in Image of PictureBox, not on PictureBox control:

    private void timer1_Tick(object sender, EventArgs e)
    {
        Image img = new Bitmap(width, height);
        Graphics g = Graphics.FromImage(img);
        g.FillRectangle(Brushes.Green, Convert.ToInt32(x), Convert.ToInt32(y), 10, 10);
        pictureBox1.Image = img;
    }

EDIT

if you want to draw on PictureBox control without flickering, put your drawing on pictureBox1.Paint event as follow:

    private void Form1_Load(object sender, EventArgs e)
    {
        // Your Solution
        int x = 0, y = 0;
        pictureBox1.Paint += new PaintEventHandler(delegate(object sender2, PaintEventArgs e2)
        {
            e2.Graphics.FillRectangle(Brushes.Green, x, y, 10, 10);
        });

        // Test
        buttonTest1.Click += new EventHandler(delegate(object sender2, EventArgs e2)
        {
            x++;
            pictureBox1.Invalidate();
        });

        buttonTest2.Click += new EventHandler(delegate(object sender2, EventArgs e2)
        {
            for (x = 0; x < pictureBox1.Width - 10; x++)
            {
                System.Threading.Thread.Sleep(50);
                pictureBox1.Invalidate();
                pictureBox1.Refresh();
            }
        });

        buttonTest3.Click += new EventHandler(delegate(object sender2, EventArgs e2)
        {
            System.Windows.Forms.Timer t = new System.Windows.Forms.Timer();
            t.Tick += new EventHandler(delegate(object sender3, EventArgs e3)
            {
                if (x <= pictureBox1.Width - 10)
                    x++;
                pictureBox1.Invalidate();
            });
            t.Enabled = true;
            t.Interval = 50;
        });
    }