Convert Character Set By VBA

I wanted convert character set on VBA.
So I coded.

'**************************************************
'
'   指定文字コードに変換した文字列を返す
'   @return String
'   @exception
'
'**************************************************

Public Function GetTextConvertedFromBinaryArrayWithSpecificCharacterSet(argExecutedPoint As String, argArrByte As Variant, argCharacterSet As String) As String
    Dim executedPoint As String
    executedPoint = argExecutedPoint & FPR_MODULE_NAME & "GetTextConvertedWithSpecificCharacterSet"
    On Error GoTo ERROR_STEP:

    '//////////////////////////////////////// specific //////////////////////////////////////////////////////////

    Dim ret As String
    Dim objStream As New ADODB.Stream
    Dim hasOpened As Boolean
    
    With objStream
        Call .Open
        hasOpened = True
        .Type = ADODB.StreamTypeEnum.adTypeBinary
        .Write (argArrByte)
    
        .Position = 0
        .Type = ADODB.StreamTypeEnum.adTypeText
        .Charset = argCharacterSet
        ret = .ReadText()
        
        Call .Close
        hasOpened = False
    End With
    Set objStream = Nothing
    GetTextConvertedFromBinaryArrayWithSpecificCharacterSet = ret

    '//////////////////////////////////////// specific //////////////////////////////////////////////////////////

    Exit Function
ERROR_STEP:
    If True = hasOpened Then
        objStream.Close
        Set objStream = Nothing
    End If
    Call ReRaiseErrorObject(executedPoint, Err)
End Function