winform鼠标滚轮事件

#region 进入窗体时加载

public FormAlarmInfoQuery()
{
    InitializeComponent();
    pictureBox1.ImageLocation = "f:\1.jpg";

         this.MouseWheel += new System.Windows.Forms.MouseEventHandler(this.panel1_MouseWheel);
         //判断是否已安装带滚轮的鼠标
    //SystemInformation.MouseWheelPresent.ToString();
    //获取鼠标滚轮在滚动时所获得的行数
    //SystemInformation.MouseWheelScrollLines.ToString();
    //判断该操作系统是否支持滚轮鼠标
    //SystemInformation.NativeMouseWheelSupport.ToString(); 
}

#endregion

private void panel1_MouseWheel(object sender, System.Windows.Forms.MouseEventArgs e)
{
    MessageBox.Show("滚动事件已被捕捉");
    System.Drawing.Size t = pictureBox1.Size;
    t.Width += e.Delta;
    t.Height += e.Delta;
    pictureBox1.Width = t.Width;
    pictureBox1.Height = t.Height;
}

下面是鼠标控制音乐播放器音量事件

        public Form1()
        {
            InitializeComponent();
            this.btnjin.MouseWheel += new MouseEventHandler(btnjin_MouseWheel);

        }
        int m1=30;
        private void btnjin_MouseWheel(object sender, System.Windows.Forms.MouseEventArgs e) 
        {
            if(m1>=0&&m1<=100)
            {
                m1 += e.Delta / 24;
                if (m1 > 100)
                {
                    m1 = 100;
                }
                else if (m1 < 0)
                {
                    m1 = 0;
                }
                lblvol.Width = (60 / 20) * m1 / 5;
                Music.settings.volume = m1 ;
            }
            

        }

        private void btnjin_MouseEnter(object sender, EventArgs e)
        {
            panel2.Visible = true;
        }

        private void btnjin_MouseLeave(object sender, EventArgs e)
        {
            panel2.Visible = false;
        }