主题：[求助]PDF不能在窗口中显示

求大神帮诊断一下这段代码：

Dim wbr As WinForm.WebBrowser = e.Form.Controls("0001-PDF")
Dim tmp As String = ProjectPath & "Attachments\MB01-清单计价表.xls"
Dim rpt As String = ProjectPath & "Reports\MB01-清单计价表.pdf"
Dim Book As New XLS.Book(tmp)
Book.Build()
Book.SaveToPDF(rpt)
wbr.Address = rpt

运行之后，PDF不能正常显示。