Changing the backgroundimage of a MainFrame / Control

You can change the BackgroundImage of a form by following code

 private void button1_Click(object sender, EventArgs e)
        {
            if (this.BackgroundImage == null)
                this.BackgroundImage = new Bitmap(Properties.Resources.image1);
            else
                this.BackgroundImage = null;           
        }      

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Hope above help !

Doanh