修改鼠标十字光标代码,使其位于窗体顶部?

code 可以添加以显示在鼠标指针处相交的线(十字光标)。问题是表单上的控件(如listview、splitcontainer、buttons)不显示(或部分隐藏)行。

我如何修改下面的代码以显示窗体上所有控件的顶部(置于前面…)?

int lastX = 0;
int lastY = 0;
private void Form1_MouseMove(object sender, MouseEventArgs e)
{
Region r = new Region();
r.Union(new Rectangle(0, lastY, this.Width, 1));
r.Union(new Rectangle(lastX, 0, 1, this.Height));
this.Invalidate(r);
this.Update();
Graphics g = Graphics.FromHwnd(this.Handle);

g.DrawLine(Pens.Chocolate, 0, e.Y, this.Width, e.Y);
g.DrawLine(Pens.Chocolate, e.X, 0, e.X, this.Height);
lastX = e.X;
lastY = e.Y;
}

private void Form1_MouseLeave(object sender, EventArgs e)
{
this.Invalidate();
}