Hi

I need to rewrite the following COM Server program from VB6 to VFP9. The COM client application calls my VFP COM server and pass an object reference. The object has methods that can be called to return various values to my VFP COM server.

My problem is that in my VFP9 COM server, passing by reference doesn't work. Is there something I must specify in my VFP COM server class to allow passing by reference?

The VB6 and translated VFP9 codes below. Please see my comments in my VFP9 code to see where it doesn't work. Your advice much appreciated. Thanks



VERSION 1.0 CLASS
BEGIN
MultiUse = -1 'True
Persistable = 0 'NotPersistable
DataBindingBehavior = 0 'vbNone
DataSourceBehavior = 0 'vbNone
MTSTransactionMode = 0 'NotAnMTSObject
END
Attribute VB_Name = "ExportClass"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = True
Attribute VB_PredeclaredId = False
Attribute VB_Exposed = True

'***************************************************************
' This method called by Reader for every page in selection (valid for export)
' Reader fills fieldsObj (IDispatch) with information from currently exported page
' fieldsObj has methods
' Function GetFieldsCount() As Long - return number of fields
' Sub GetFieldsNames( fieldsNames as Variant ) - fills fieldsNames with names of fields
' Sub GetFieldsTypes( fieldsTypes As Variant ) - fills fieldTypes with types of fields
' Sub GetFieldByIndex(ByVal Index as long, OutValue as Variant )
' Sub GetFieldByName(ByVal Name as String, OutValue as Variant )
'

Option Explicit

Public Sub ExportMethod(ByVal fieldsObj As Object)
Dim fieldIndex As Integer
Dim fieldValue As Variant
Dim fieldsNames As Variant ' array of page fieldValue names
Dim fieldsTypes As Variant
Dim fieldDescr As String
On Error GoTo err_h
'getting page fields names into array of variants for checks or reference
fieldsObj.GetFieldsNames fieldsNames
fieldsObj.GetFieldsTypes fieldsTypes

'iterate fields, determine there types and process
For fieldIndex = 0 To fieldsObj.GetFieldsCount - 1
'get value of fieldValue into fieldValue variable (Variant)
fieldsObj.GetFieldByIndex fieldIndex, fieldValue
'........... some codes go here
'........... some codes go here
Next fieldIndex
Exit Sub
End Sub

My VFP code as follows :

DEFINE CLASS A2FORM AS Session OLEPUBLIC
cField_Name = ''
cField_Value = ''
cField_Type = ''

PROCEDURE Export_Data(toForm AS Object)
LOCAL lnFields, lni
PRIVATE lcValue AS Variant

lnFields = toForm.GetFieldsCount() && This call works beautifully!
IF lnFields >0
LOCAL ARRAY laFields[lnFields] as Variant
COMARRAY(toForm,10)
laFields = 'None'
toForm.GetFieldsNames(@laFields) && Problem here. laFields cannot be
&& initialised although passed
&& by reference

FOR lni = 1 TO lnFields
This.cfield_Value = .F.
lcValue = .F.
toForm.GetFieldByIndex(lni,@lcValue) && Problem here. lcValue cannot be
&& initialised although passed by reference
ENDFOR
ENDIF
ENDPROC

ENDDEFINE