vb编程题！！！！！急急急！！！！！！！！

this.panel1.BackColor = Color.Red; if (this.panel1.BackColor == Color.Red) { this.panel1.BackColor = Color.Green; } if (this.panel1.BackColor == Color.Green) { this.panel1.BackColor = Color.Yellow; } Button1.ForeColor = this.panel1.Back