PropVariantToInt32Vector function (propvarutil.h)

Extracts a vector of long values from a PROPVARIANT structure.

Syntax

PSSTDAPI PropVariantToInt32Vector(
  [in]  REFPROPVARIANT propvar,
  [out] LONG           *prgn,
  [in]  ULONG          crgn,
  [out] ULONG          *pcElem
);

Parameters

[in] propvar

Type: REFPROPVARIANT

Reference to a source PROPVARIANT structure.

[out] prgn

Type: LONG*

Points to a buffer containing crgn   LONG values. When this function returns, the buffer has been initialized with pcElem   LONG elements extracted from the source PROPVARIANT.

[in] crgn

Type: ULONG

Size of the buffer pointed to by prgn in elements.

[out] pcElem

Type: ULONG*

When this function returns, contains the count of LONG elements extracted from source PROPVARIANT structure.

Return value

Type: HRESULT

This function can return one of these values.

Remarks

This helper function is used in places where the calling application expects a PROPVARIANT to hold a vector of LONG values with a fixed number of elements.

If the source PROPVARIANT has type VT_VECTOR | VT_I4 or VT_ARRAY | VT_I4, this helper function extracts up to crgn   LONG values and places them into the buffer pointed to by prgn. If the PROPVARIANT contains more elements than will fit into the prgn buffer, this function returns an error and sets pcElem to 0.

Examples

The following example, to be included as part of a larger program, demonstrates how to use PropVariantToInt32Vector to access an Int32 vector value in a PROPVARIANT.

// PROPVARIANT propvar;
// Assume the variable propvar is initialized and valid
LONG rgLongs[4]; // The application is expecting propvar to hold 4 LONGs in a vector
ULONG cElems;
HRESULT hr = PropVariantToInt32Vector(propvar, rgLongs, ARRAYSIZE(rgLongs), &cElems);
if (SUCCEEDED(hr))
{
     if (cElems == ARRAYSIZE(rgLongs))
     {
         // The application got 4 LONGs which are now stored in rgLongs
     }
     else
     {
         // The application got cElems which are stored in the first cElems elements of rgLongs
     }
}

Requirements

See also

InitPropVariantFromInt32Vector

PropVariantGetInt32Elem

PropVariantToInt32

PropVariantToInt32VectorAlloc

VariantToInt32Array