C#代码实现：

private void button1_Click(object sender, EventArgs e)
{
    this.WindowState = FormWindowState.Maximized;
    this.notifyIcon1.Visible = true;
}

private void button2_Click(object sender, EventArgs e)
{
    this.WindowState = FormWindowState.Minimized;
    this.notifyIcon1.Visible = true;
}
private void button3_Click(object sender, MouseEventArgs e)
{
    this.WindowState = FormWindowState.Normal;
    this.Visible = true;
}

C#程序实现窗体的最大化/最小化