Paul,
Your question sounds a little too simple, so I'm going to assume there's
something I'm unaware of.
But to go by your question, create a property in your user control
Public Property CDataSource() As DataSet
Get
Return _ds
End Get
Set(ByVal Value As DataSet)
_ds = Value
End Set
End Property
And from your class,
MyControlName.CDataSource = ds
Of course, you'd have to add some mechanism to check, in the control,
whether a dataset has been assigned or not.
-Altaf