Sending an array from VC++ to a VB OCX

[selad]

Hello all,

I have a problem, which is bugging me for a few weeks now and I hope I will find the answer here.

I wrote an activex control in visual basic. The activex control has a method that one of the arguments is a “Variant” that expects an array.
Now I’m trying to use the control from VC++. The problem is how should I send the array from VC++ to the control.

For example, I attached a demo OCX (proTest.ocx) that have only one method (I had some problems attaching the file so it can be found here
http://www.optiwater.com/proTest.zip):

Public Function TEST(varArray As Variant) As Integer



The method expects varArray to be an array (no specific size). The array’s elements are shown in a message box – so use small arrays.

I would be very grateful for any ideas,

Elad Salomons

[steveconner]

Here is a C++ code snippet....

Create an ATL DLL, then a simple object add a method to return a VARIANT ([out, retval] VARIANT* pVal) then

#include <comdef.h>

STDMETHODIMP CTSA::GetSafeArray(VARIANT *pVal)
{
SAFEARRAYBOUND rgsabound[1];
HRESULT hr = S_OK;

_variant_t var[5];
var[0].vt = VT_I4;
var[0].lVal = 500;
var[1] = L"This is String 1";
var[2] = L"This is String 2";
var[3].vt = VT_I4;
var[3].lVal = 324412;
var[4] = L"This is String 3";
const int varsize = sizeof var / sizeof var[0];

rgsabound[0].lLbound = 0;
rgsabound[0].cElements = varsize;

pVal->vt = (VT_ARRAY | VT_VARIANT);
pVal->parray = SafeArrayCreate(VT_VARIANT, 1, rgsabound);

for (long x = 0; x < varsize && SUCCEEDED(hr); x++)
{
hr = SafeArrayPutElement(pVal->parray, &x, &var[x]);
}

return hr;
}


so From VB ...

Dim X As TESTSAFEARRAYLib.TSA
Set X = New TESTSAFEARRAYLib.TSA

Dim Y As Variant
Y = X.GetSafeArray

MsgBox (Y(3))


Hope this helps ....

Steve Conner