As a test, I decided to change the data type of the array that I am passing to char instead of byte, and use COMARRAY(..., 11). I had been using COMARRAY all along. So, I don't think that is the difference. In any case, this appears to work.

But, will it work without COMARRAY in a C++ client?

Any other thoughts or suggestions?
Thanks,
Jim


>What am I doing wrong??
>
>Here is a link to an MSDN example that addresses this
>
>

>http://msdn.microsoft.com/en-us/library/aa979305(v=vs.71).aspx
>

>
>It creates an array of doubles, calls a VFP COM server to calculate the determinant. It looks to me that I am doing a very analogous thing.
>
>
>
>>In other parts of my COM server, I pass parameters by reference. Here is another procedure in the server that works fine both from VFP and C++ clients:
>>
>>

>>PROCEDURE GetDatFilesFromvFBDPatVisits(sFBDDataSource AS String , nPatientNo AS Integer @, nVisitID as Integer @, ;
>>		nFileID AS Integer @, sFilename AS String @) 
>>

>>
>>And, I call this by
>>

>>Result = Thisform.oNPVD.GetDatFilesFromFBDPatVisits("FBD on JIM", @nPatientNo, @nVisitID, @nFileID, @cFilename)	
>>

>>
>>But, none of these are byte arrays.
>>
>>
>>>In VFP you need to call it by reference, e.g.
>>>
>>>DIMENSION aBlobData[nFileSize] AS Byte
>>>thisform.oNPVD.GetvFBDBlob(nFileID, @aBlobData) -- array populated with .F. at present
>>>
>>>However, I think there may be problems related with COM and passing parameters by reference - I don't recall right now.
>>>
>>>>>>Naomi,
>>>>>>
>>>>>>Thanks for your quick response.
>>>>>>
>>>>>>I have done the things you suggested. Again, it works when I create the object directly for the PRG file. When I build the COM EXE, i no longer get the error that aBlobData is undefined. However, at runtime, I get the error in the FOR loop saying "Invalid subscript reference".
>>>>>>
>>>>>>Jim
>>>>>>
>>>>>>
>>>>>Can you post code that invokes this function and also the code that checks the array size.
>>>>
>>>>Here is the code that invokes the function:
>>>>

>>>>DIMENSION aBlobData[nFileSize] AS Byte
>>>>thisform.oNPVD.GetvFBDBlob(nFileID, aBlobData)
>>>>

>>>>
>>>>Here is the code at the beginning of GetvFBDBlob:
>>>>

>>>>FUNCTION GetFBDBlob(nFileID AS Integer, aBlobData AS Byte ) AS Integer
>>>>   EXTERNAL ARRAY aBlobData
>>>>   LOCAL nResult AS Integer, nBlobSize AS Integer
>>>>   MESSAGEBOX("length of aBlobData: " + STR(ALEN(aBlobData)))
>>>>

>>>>
>>>>When I build the COM, and then run my VFP client, I get an error message saying "ABLOBDATA is not an array"
>>>>
>>>>I have tried calling with and without '@" in the call: GetvFBD(nFileID, @aBlobData) and GetvFBD(nFileID, aBlobData). Get the same error message.
>>>>
>>>>
>>>>Jim