[RESOLVED] Pass Integer Array to C++ Active Control

[sanx72]

Hi,

I'm using VB.NET within Visual Studio 2008.

I have a ActiveX control on my form that contains a method that takes an Array. In VB6 I just passed in the array and it was populated OK. When I do the same in VB.NET, I get a result but the value of each index appears to be a pointer.

Here is the C++ method code...

void CMyCtrl::GetRowInfo(const VARIANT FAR& vArray, short sNumRows)
{
// Declaretemp array to put the row list into
short asRowList[24];

// populate temp array here

// Declare a SAFEARRAY to manipulate the VARIANT
SAFEARRAY FAR* FAR* ppsa = NULL;

short sCounter, sVal;

long ai[1]; // 1-D array index

// Variant access macro V_ARRAYREF(X) = V_UNION(X, pparray) = ((X)->pparray)
ppsa = V_ARRAYREF(&vArray);

// Check that we're only passing back a max of 24 row heights
sNumRows = sNumRows > LueScreenHigh ? LueScreenHigh : sNumRows;

// Copy the correct number of rows from psnRowList into a SAFEARRAY
for (sCounter = 0; sCounter < sNumRows; sCounter++)
{
ai[0] = sCounter;

sVal = asRowList[sCounter];

SafeArrayPutElement(*ppsa, ai, &sVal);
}

return;
}

Here is the VB code (same VB6 and VB.NET...

Dim maintRowList(0 To 23) As Integer
AxMyCtrl.GetRowInfo(maintRowList, 24)

In VB6, the value of maintRowList(0) is in the range 0 to Windows screen height (its a pixel value)

In VB.NET the value of maintRowList(0) is a value that looks like a pointer to me (e.g 285671429).

In VB.NET, the type of the 1st parameter is Object. In VB6 it is a Variant.

I've tried AxMyCtrl.GetRowInfo(maintRowList(0), 24) and got the same result.

I think I need to get a pointer to either the array or the first element of the array but I can't see a way to do that.

Can anyone suggest how I can pass an array to this type of C++ ActiveX method?

BTW - I cannot change the ActiveX code so the solution must be within VB.NET.

Thanks
Sanx

[sanx72]

The solution is that in VB6 the Integers are 16-bit so I changed the definition of the array in VB.NET to...

Dim maintRowList(0 To 23) As Int16

...and all is well.

Sorry if I wasted anyone's time!