Option Explicit Public Function function01(ByRef s1 As String, ByRef s2 As String) As Integer Dim result As Integer result = 1 s2 = s1 & Trim(s2) function01 = result End Function Public Function function02(ByRef s1 As String) As String function02 = "http://" & s1 End Function- build dll: File - Make SampleDll.dll
aa = CREATEOBJECT("SampleDll.SampleClass") ? aa.function02("www") bb = "ccc" ? aa.function01("http://", @bb) ? bbBoth function01 and function02 do not make much sense :) just an example. The function02 has definitely better interface.