WinForm中Panel实现用鼠标操作滚动条

由于在WinForm中Panel不能直接响应鼠标的滚动事件，只好采用捕获窗体的滚动事件。
方法如下：
在窗体的Load事件注册滚动事件，并增加对应的方法

private void FormSample_Load(object sender, EventArgs e)
{

//注册事件
this.MouseWheel += new MouseEventHandler(FormSample_MouseWheel);
}

/// <summary>
/// 滚动方法
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
void FormSample_MouseWheel(object sender, MouseEventArgs e)
{
//获取光标位置
Point mousePoint = new Point(e.X,e.Y);
//换算成相对本窗体的位置
mousePoint.Offset(this.Location.X, this.Location.Y);
//判断是否在panel内
if (pnlDownload.RectangleToScreen(pnlDownload.DisplayRectangle).Contains(mousePoint))
{
//滚动
pnlDownload.AutoScrollPosition = new Point(0, pnlDownload.VerticalScroll.Value - e.Delta);
}
}