Dim doc As New PrintDoc \'定义一个新报表
Dim rt As New prt.RenderTable \'定义一个新表格
Dim tb As Table = Tables("往来单位")
rt.SplitHorzBehavior = prt.SplitBehaviorEnum.SplitIfNeeded \'表格宽度超出页宽时,可以水平换页
For c As Integer = 0 To tb.Cols.Count -1 \'逐列设置和填入内容
    rt.Cells(0,c).Text = tb.Cols(c).Name \'列名作为标题
    rt.Cells(0,c).Style.TextAlignHorz = prt.AlignHorzEnum.Center \'标题内容水平居中
    rt.Cols(c).Width = tb.Cols(c).PrintWidth \'列宽等于实际列宽
    If tb.Cols(c).IsNumeric OrElse tb.Cols(c).IsDate Then \'如果是数值或日期列
        rt.Cols(c).Style.TextAlignHorz = prt.AlignHorzEnum.Right \'数据水平靠右
    End If
    For r As Integer = 0 To tb.Rows.Count -1 \'开始填入该列内容
        rt.Cells(r + 1, c).Text = tb(r,c)
    Next
Next

doc.Body.Children.Add(rt) \'将表格加入到报表
doc.Preview()

这段代码设计出来的专业报表为什么会有水印呀。