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wiasReadMultiple function (wiamdef.h)

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The wiasReadMultiple function retrieves multiple property values from a WIA item.

Syntax

HRESULT wiasReadMultiple(
  [in]            BYTE           *pWiasContext,
                  ULONG          ulCount,
  [in]            const PROPSPEC *ps,
  [out]           PROPVARIANT    *pv,
  [out, optional] PROPVARIANT    *pvOld
);

Parameters

[in] pWiasContext

Pointer to a WIA item context.

ulCount

Specifies the number of properties to read.

[in] ps

Pointer to the first element of an array of PROPSPEC structures, containing the properties to read.

[out] pv

Pointer to the first element of an array of PROPVARIANT structures. Upon return, these structures contain new values for the properties.

[out, optional] pvOld

Pointer to the first element of an array of PROPVARIANT structures previously allocated by the minidriver. Upon return, the array contains the previous values of the property data. If this information is not needed, this parameter can be set to NULL.

Return value

On success, the function returns S_OK.

If the function fails, it returns a standard COM error or one of the WIA error codes.

Remarks

This function reads multiple properties from a WIA item. When the call succeeds, the minidriver must call PropVariantClear on each element in the array specified by the pv parameter. See IPropertyStorage::ReadMultiple for more information.

Requirements

Requirement Value
Target Platform Desktop
Header wiamdef.h (include Wiamdef.h)
Library Wiaservc.lib
DLL Wiaservc.dll

See also

wiasWriteMultiple