InitVariantFromVariantArrayElem function

Initializes a VARIANT structure with a value stored in another VARIANT structure.

Syntax


HRESULT InitVariantFromVariantArrayElem(
  _In_  REFVARIANT varIn,
  _In_  ULONG      iElem,
  _Out_ VARIANT    *pvar
);

Parameters

varIn [in]

Type: REFVARIANT

Reference to the source VARIANT structure.

iElem [in]

Type: ULONG

Index of one of the source VARIANT structure elements.

pvar [out]

Type: VARIANT*

When this function returns, contains the initialized VARIANT structure.

Return value

Type: HRESULT

If this function succeeds, it returns S_OK. Otherwise, it returns an HRESULT error code.

Remarks

This helper function works for VARIANT structures of the following types:

  • VT_BSTR
  • VT_BOOL
  • VT_I2
  • VT_I4
  • VT_I8
  • VT_U12
  • VT_U14
  • VT_U18
  • VT_DATE
  • VT_ARRAY | (any one of VT_BSTR, VT_BOOL, VT_I2, VT_I4, VT_I8, VT_U12, VT_U14, VT_U18, VT_DATE)

Additional types may be supported in the future.

This function extracts a single value from the source VARIANT structure and uses that value to initialize the output VARIANT structure. The calling application must use VariantClear to free the VARIANT referred to by pvar when it is no longer needed.

If the source VARIANT is an array, iElem must be less than the number of elements in the array.

If the source VARIANT has a single value, iElem must be 0.

If the source VARIANT is empty, this function always returns an error code.

You can use VariantGetElementCount to obtain the number of elements in the array or array.

Examples

The following example, to be included as part of a larger program, demonstrates how to use InitVariantFromVariantArrayElem in an iteration statement to access the values in a VARIANT.


// VARIANT var;
// Assume var is initialized and valid.
UINT cElem = VariantGetElementCount(var);
HRESULT hr = <mark type="const">S_OK</mark>;

for (UINT iElem = 0; SUCCEEDED(hr) && iElem < cElem; iElem ++)
{
    VARIANT varElem = {0};

    hr = InitVariantFromVariantArrayElem(var, iElem, &varElem);

    if (SUCCEEDED(hr))
    {
        // varElem is now valid.
        VariantClear(&varElem);
    }
}

Requirements

Minimum supported client

Windows XP with SP2, Windows Vista [desktop apps only]

Minimum supported server

Windows Server 2003 with SP1 [desktop apps only]

Redistributable

Windows Desktop Search (WDS) 3.0

Header

Propvarutil.h

Library

Propsys.lib

DLL

Propsys.dll (version 6.0 or later)

See also

VariantGetElem
InitPropVariantFromPropVariantVectorElem

 

 

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