如何点击一个按钮，弹出选择文件对话框，选择图片后自动上传并显示在image控件中？

用户一个pictureBox，button，openFileDialog。      
this.pictureBox1.Image = img;
this.BackgroundImage = img;
这两行都可以显示图像。

 private void button1_Click(object sender, EventArgs e)
        {
            if (this.openFileDialog1.ShowDialog() != DialogResult.OK)
                return;
            try
            {
                Image img = Image.FromFile(this.openFileDialog1.FileName);
                this.pictureBox1.Image = img;
                this.BackgroundImage = img;
            }
            catch (System.Exception ex)
            {
                MessageBox.Show("ERROR！");
            }
        }