IEnumVARIANT::Next

This method attempts to get the next celt items in the enumeration sequence, and return them through the array pointed to by rgVar.

At a Glance

Syntax

HRESULT Next( unsigned long celt, VARIANT FAR* rgVar,
unsigned long FAR* pCeltFetched );

Parameters

celt

Number of elements to be returned.

rgVar

Array of at least size celt in which the elements are to be returned.

pCeltFetched

Pointer to the number of elements returned in rgVar, or NULL.

Return Values

One of the values described in the following table is returned.

Remarks

If fewer than the requested number of elements remain in the sequence, Next returns only the remaining elements. The actual number of elements returned is passed through *pCeltFetched, unless it is NULL.

Example

The following code implements IEnumVariant::Next for collections in the Lines sample file Enumvar.cpp.

STDMETHODIMP
CEnumVariant::Next(ULONG cElements, VARIANT FAR* pvar, ULONG FAR* pcElementFetched)
{
   HRESULT hr;
   ULONG l;
   long l1;
   ULONG l2;

   if (pcElementFetched != NULL)
      *pcElementFetched = 0;

   for (l=0; l<cElements; l++)
      VariantInit(&pvar[l]);

   // Retrieve the next cElements elements.
   for (l1=m_lCurrent, l2=0; l1<(long)(m_lLBound+m_cElements) && 
      l2<cElements; l1++, l2++)
   {
      hr = SafeArrayGetElement(m_psa, &l1, &pvar[l2]); 
      if (FAILED(hr))
         goto error; 
   }
   // Set count of elements retrieved.
   if (pcElementFetched != NULL)
      *pcElementFetched = l2;
   m_lCurrent = l1;

   return  (l2 < cElements) ? ResultFromScode(S_FALSE) : NOERROR;

error:
   for (l=0; l<cElements; l++)
      VariantClear(&pvar[l]);
   return hr;
}