Crystal report 9 vs visual basic

[beely]

hi guys, i have tried to use vb code to interacting with the CRViewer 9 with the code statement

Dim Appl As New CRAXDRT.Application
Dim Report As New CRAXDRT.Report
Private Sub Form_Load()
    Set Report = Appl.OpenReport(ReportFile)
    CRViewer91.ReportSource = Report
    CRViewer91.ViewReport
End Sub
Private Sub Form_Resize()
    With CRViewer91
        .Top = 0
        .Left = 0
        .Width = Me.ScaleWidth
        .Height = Me.ScaleHeight
    End With
End Sub

however, the dim part occur error , and display error about the ARAXDRT is not defined. any other solution ? thanks .