請問一下大家...我想要點擊時可以切換button的圖片...但是

private void button3_Click(object sender, EventArgs e)
        {
            if (button2.BackgroundImage == Properties.Resources.英文開1)
            {
                button2.BackgroundImage = Properties.Resources.英文關1;
            }
            else
            {
                button2.BackgroundImage = Properties.Resources.英文開1;
            }
        }//這樣是不行的...為何??
        
        
        
        private void button2_Click(object sender, EventArgs e)
        {
            if (button2.Text == "start") {
                button2.Text = "end";
            }
            else
            {
                button2.Text = "start";
            }
        }//這樣卻是可以的??