passing array to OCX

[mitch]

Hi, could anyone help me with the following problem?

I have an ActiveX control developed using Visual Studio 6.0 and it has
a method declared in the .odl file as follows:

void GetEmptyVectorDatumVariantArray(long nNumData, VARIANT*
pVariantArrayRequired);

The body of this method is simply:

SAFEARRAYBOUND sab = {nNumData, 0};

SAFEARRAY* pSaCreated = SafeArrayCreate(VT_R8, 1, &sab);

pVariantArrayRequired->vt = VT_ARRAY | VT_R8;
pVariantArrayRequired->parray = pSaCreated;

So we see that the net result is a method which sets up and returns an
empty safearray.

Now I need to pass a safearray of data to the activex control, so I
have one final method defined in it as foolows in the .odl:

void SetVectorField(VARIANT* vtArrayVectorData, long nNumElements);

the body of this is simply:

SAFEARRAY* psaVectorData = vtArrayVectorData->parray;

double* pRawData = NULL;

SafeArrayAccessData(psaVectorData, (void**)&pRawData);

m_p3DWnd->SetVectorField(pRawData,nNumElements); // Pass data to
another class

SafeArrayUnaccessData(psaVectorData);

SafeArrayDestroy(psaVectorData);

So we see that this simply takes a safearray and passes on the data to
another class.

Finally I call the above to methods in c++ as follows:

VARIANT vtArrayPositions;
VariantClear(&vtArrayPositions);
m_ptrControl->GetEmptyVectorDatumVariantArray(m_nNumTestDatum s,
&vtArrayPositions);

SAFEARRAY* psa = vtArrayPositions.parray;

double* pVectorDatums = NULL;
SafeArrayAccessData(psa, (void**)&pVectorDatums);

for(int nDatum = 0; nDatum < m_nNumTestDatums; nDatum++)
{
pVectorDatums[nIndexBase] = 1.0;
}

::SafeArrayUnaccessData(psa);

m_ptrControl->SetVectorField(&vtArrayPositions,m_nNumTestDatu ms );

So basically I fill the returned empty array with 1's and then pass it
to the activex control.

I all works perfectly - in c++.

QUESTION:
How can I call these two methods from c#?