Passing Multi-Dimensional Arrays Between PBDLL and VB6

[Gene Chiaramonte]

I am trying to pass a 2D VB array of doubles to a PBDLL SUB that
sums each row. I keep getting an error that "The object invoked
has disconnected from it's clients."

Here is an example that illustrates the problem. Anyone know what
is wrong?

Thanks,

Gene


SUB SumArray ALIAS "SumArray" (a AS DWORD, r AS DWORD) EXPORT

' sum each row in the 2D array "a"
' and return the results in array "r"

REGISTER sum AS EXT
REGISTER row AS LONG
REGISTER col AS LONG
DIM vb AS DWORD
DIM rows AS LONG
DIM cols AS LONG

rows = vbArrayUBound(a, 1)
cols = vbArrayUBound(a, 2)

vb = vbArrayFirstElem(a)
DIM a(1 TO rows, 1 TO cols) AS DOUBLE AT vb

vb = vbArrayFirstElem(r)
DIM r(1 TO rows) AS DOUBLE AT vb

FOR row = 1 TO rows
sum = 0.0
FOR col = 1 TO cols
sum = sum + a(row,col)
NEXT col
r(row) = sum
NEXT row

END SUB

------------------
Gene

[Lance Edmonds]

Assuming you are passing the array descriptor from VB (you did not post the VB code), the PB code should be receiving the DWORD BYVAL, since you want to get the address of the array descriptor that VB is passing to PB.

Without the BYVAL DWORD in the PB code, PB is taking the actual value in the memory within the descritor and treating it as the address of the descriptor table.

Try this:

SUB SumArray ALIAS "SumArray" (BYVAL a AS DWORD, BYVAL r AS DWORD) EXPORT

------------------
Lance
PowerBASIC Support
mailto:[email protected][email protected]</A>

[Gene Chiaramonte]

Thanks for the info, I tried your suggestion
but it didn't work.

I am going by the vb sort examples,
vbsort.bas and vbsort.txt that come with PB.

The sorting function examples work fine without using byval.
If you have an example of passing a 2D array to/from VB and
PB it would be greatly appreciated.

Thanks.

Here is all the code from vb (I'm using excel to test):

Declare Sub SumArray Lib "vbsort.dll" (a#(), r#())

Private Sub CommandButton3_Click()

Dim i As Long
Dim ii As Long
Dim a(1 To 10, 1 To 5) As Double
Dim r(1 To 10) As Double

For i = 1 To 10
For ii = 1 To 5
a(i, ii) = i * ii
Next
Next

SumArray a(), r() ' error!!!

For i = 1 To 10
Sheet1.Cells(i, 1).Value = r(i)
Next

End Sub

------------------
Gene

[Tom Hanlin]

This should help!

Declare Sub SumArray Lib "vbsort.dll" [b]Alias "SumArray"[/b] (a#(), r#())

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Tom Hanlin
PowerBASIC Staff

[Gene Chiaramonte]

I tried adding Alias "SumArray" as above, but since the
alias and the sub have the same name, the vb editor
deletes the alias statement, putting it back to this:

Declare Sub SumArray Lib "vbsort.dll" (a#(), r#())

I can run the vbsort.bas SortDouble example fine with the
following declaration:

Declare Sub SortDouble Lib "vbsort.dll" (x#())

It seems to be a problem with the 2D array. Does anyone have an
example of passing a 2D array to/from vb/pbdll?

Thanks.

------------------
Gene

[Semen Matusovski]

gene --
i very recommend borje's poffs, which has nice search capabilities.
during 5 sec i found http://www.powerbasic.com/support/pb...ead.php?t=2369

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e-mail: [email protected]