Cogo Labels

[CarsonGarver1]

In attempting to display cogo labels we are trying to display radius but only when it is populated in the field via the Create COGO Fields tool in ArcCatalog.
we are trying to get something similar to cad

Function FindLabel ( [Direction], [Distance], [Radius] )
FindLabel = [Direction] & vbNewLine & [Distance] & vbNewLine & â??R = â?? &[Radius]
End Function

With this script it will put an R= on every label. How do we get it to do R= [Radius] only when radius is populated in the attribute table.

[RichardFairhurst]

In attempting to display cogo labels we are trying to display radius but only when it is populated in the field via the Create COGO Fields tool in ArcCatalog. 
we are trying to get something similar to cad 

Function FindLabel ( [Direction], [Distance], [Radius] ) 
FindLabel = [Direction] & vbNewLine & [Distance] & vbNewLine &   â??R = â?? &[Radius]
End Function 

With this script it will put an R= on every label. How do we get it to do R= [Radius] only when radius is populated in the attribute table.

Function FindLabel ( [Direction], [Distance], [Radius] )
if IsNull([Radius]) Then
FindLabel = [Direction] & vbNewLine & [Distance]
ElseIf [Radius] = 0 Then
FindLabel = [Direction] & vbNewLine & [Distance]
Else
FindLabel = [Direction] & vbNewLine & [Distance] & vbNewLine & â??R = â?? &[Radius]
End If
End Function

[CarsonGarver1]

Thank you!