主题：拖动窗口Panel1滑动条，背景图片会花屏。

 加背景图片

'加图片
Dim pnl1 As WinForm.Panel = e.Form.Controls("背景图")
pnl1.basecontrol.backgroundimage = getimage(ProjectPath & "Images\未标题-2.png")
pnl1.basecontrol.BackgroundImageLayout = Windows.Forms.ImageLayout.Stretch
pnl1.BaseControl.Gettype().GetProperty("DoubleBuffered",Reflection.BindingFlags.Instance Or System.Reflection.BindingFlags.NonPublic).SetValue(pnl1.BaseControl,True,Nothing)

'加图片
pnl1 = e.Form.Controls("panel1")
pnl1.basecontrol.backgroundimage = getimage(ProjectPath & "Images\未标题-2.png")
pnl1.basecontrol.BackgroundImageLayout = Windows.Forms.ImageLayout.Stretch
pnl1.BaseControl.Gettype().GetProperty("DoubleBuffered",Reflection.BindingFlags.Instance Or System.Reflection.BindingFlags.NonPublic).SetValue(pnl1.BaseControl,True,Nothing)

主要是后面的panel的背景并不被前面panel1锁知晓，滚动的时候，没有处理。

第二段代码是给panel1也加上一个背景图片