主题：逐行显示条码的程序报错，请问如何修改

Dim doc As New PrintDoc() '定义一个报表
Dim rt As prt.RenderText '定义一个文本对象
Dim rg As prt.RenderGraphics
Dim Bar As BarCodeBuilder
doc.Stacking = prt.StackingRulesEnum.InlineLeftToRight '设置排列方式

For i As Integer = 0 To 10
    Bar.Symbology = Barpro.Symbology.Code128
    bar.Code ="12345678901234567890"
    rg = new prt.RenderGraphics
   
    rg.X = 10
    rg.Y = 25
    bar.BarRatio = 0.8
    bar.BarHeight = 12
    bar.BarWidth = 0.3
    bar.DisplayCode =False
    bar.DrawOnCanvas(rg.Graphics,0,0,1)
   
    rg.Width = 39 '宽度为39毫米
    rg.Height = 35 '宽度为35毫米
    rg.Style.Spacing.All = 2 '设置各个方向的间隔
    rg.Style.Borders.All = New prt.Linedef(1, Color.Red) '设置边框
    rg.Style.TextAlignHorz = prt.AlignHorzEnum.Center '水平居中
    rg.Style.TextAlignVert = prt.AlignVertEnum.Center '垂直居中
   
    doc.Body.Children.Add(rg) '将文本对象加入到报表
   
Next
doc.Preview() '预览

在红色部分报错，是什么原因，帮我看下，谢谢！

还是无法执行，我把代码改了下，如下

但是无法显示出多条条码

只能显示一个

Dim doc As New PrintDoc
Dim img As prt.RenderImage
Dim Bar As New BarCodeBuilder
Dim rg As New prt.RenderGraphics
Bar.Symbology = Barpro.Symbology.Code128
Bar.BarRatio = 0.3
Bar.BarHeight = 8
Doc.Stacking = prt.StackingRulesEnum.InlineLeftToRight

For i As Integer = 1 To 4
    bar.Code = "12345678901234567890"
   
    rg = new prt.RenderGraphics
    rg.X = 10
    rg.Y = 25
    bar.BarRatio = 0.8
    bar.BarHeight = 12
    bar.BarWidth = 0.3
    bar.DisplayCode =False
    bar.DrawOnCanvas(rg.Graphics,0,0,1)
  
    Doc.Body.Children.Add(rg)
Next

Doc.Preview()