Public Sub ImportData( _
   ByVal extTable As DataTable, _
   ByVal nativeField As String, _
   ByVal extField As String _
) 

Dim instance As MapLayer
Dim extTable As DataTable
Dim nativeField As String
Dim extField As String
 
instance.ImportData(extTable, nativeField, extField)

public void ImportData( 
   DataTable extTable,
   string nativeField,
   string extField
)