Invoke Crystal report 9 from VB

[jadoogar]

I have been using Crystal report 7 in VB for report.
Now I have migrated to Crystal report 9
but the earlier code
cr.Connect = "dsn=dsname;uid=" & wusn & ";pwd=" & wpwd & ";"

cr.ReportFileName = App.Path & "\reportname.rpt"
cr.PrintReport
cr is Crviewer object
is now not working
with new cr9 viewer object
cr9viewer1.Connect = "dsn=dsname;uid=" & wusn & ";pwd=" & wpwd & ";"

cr9viewer1.ReportFileName = App.Path & "\reportname.rpt"
cr9viewer1.PrintReport where cr9viewer is
crystal report 9 viewer object

What modification is required please