主题：狐表可以设计一个按钮像QQ一样截图吗？

Dim myGraphics As Graphics = basemainform.CreateGraphics()

Dim s As new Size(916, 355) '截取的大小

Dim bit As New Bitmap(s.Width, s.Height, myGraphics)

Dim memoryGraphics As Graphics = Graphics.FromImage(bit)

memoryGraphics.CopyFromScreen(Forms("产品尺寸制作").BaseForm.Left, Forms("产品尺寸制作").BaseForm.Top, 50, 50,s) '截取的开始位置,坐标(100, 200)

bit.save(Tables("商品库").Current("商品信息_文件地址") & "\qqqq.jpg" )

.NET Framework 版本：2.0.50727.5477

Foxtable 版本：2014.3.8.1

错误所在事件：窗口,窗口1,Button1,Click

详细错误信息：

未将对象引用设置到对象的实例。

Dim myGraphics As Graphics = basemainform.CreateGraphics()

Dim tb As WinForm.TabControl = e.Form.Controls("TabControl1")

Dim s As new Size(1,1)

Dim pl As WinForm.Panel

If tb.SelectedPage.Text="Page1" Then

    pl=e.Form.Controls("Panel1")

    s= new Size(pl.Width ,pl.Height)

Else If tb.SelectedPage.Text="Page2" Then

    pl=e.Form.Controls("Panel2")

    s= new Size(pl.Width ,pl.Height)

End If

Dim myGraphics As Graphics = basemainform.CreateGraphics()

Dim s As new Size(916, 355) '截取的大小

Dim bit As New Bitmap(s.Width, s.Height, myGraphics)

Dim memoryGraphics As Graphics = Graphics.FromImage(bit)

memoryGraphics.CopyFromScreen(Forms("产品尺寸制作").BaseForm.Left, Forms("产品尺寸制作").BaseForm.Top, 50, 50,s) '截取的开始位置,坐标(100, 200)

bit.save(Tables("商品库").Current("商品信息_文件地址") & "\qqqq.jpg" )