IEnumVARIANT::Next (Windows CE 5.0)

2012-09-14

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

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

Parameters

celt
[in] Number of elements to be returned.
rgVar
[out] Array of at least size celt in which the elements are to be returned.
pCeltFetched
[out] Pointer to the number of elements returned in rgVar, or NULL.

Return Values

If the number of elements returned is celt, the return value is S_OK.

If the number of elements returned is less than celt, the return value is S_FALSE.

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 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;
}

Requirements

OS Versions: Windows CE 2.0 and later.
Header: Oaidl.h, Oaidl.idl.
Link Library: Oleaut32.lib, Uuid.lib.

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