wiasReadPropStr function (wiamdef.h)
The wiasReadPropStr function retrieves a string property value from a WIA item.
Syntax
HRESULT wiasReadPropStr(
[in] BYTE *pWiasContext,
PROPID propid,
[out] BSTR *pbstr,
[out, optional] BSTR *pbstrOld,
BOOL bMustExist
);
Parameters
[in] pWiasContext
Pointer to a WIA item context.
propid
Specifies the property identifier.
[out] pbstr
Pointer to a memory location that receives the first byte of the property's string value.
[out, optional] pbstrOld
Pointer to a memory location that receives the first byte of the property's previous value. If this information is not needed, set this parameter to NULL.
bMustExist
Indicates whether the property must exist. If set to TRUE, the property must exist; if set to FALSE, the property does not have to exist.
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_XXX errors (described in the Microsoft Windows SDK documentation).
Remarks
When the minidriver has completed using the string it received from this function, it must deallocate the memory used for the string.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Available in Microsoft Windows Me and in Windows XP and later versions of the Windows operating systems. |
| Target Platform | Desktop |
| Header | wiamdef.h (include Wiamdef.h) |
| Library | Wiaservc.lib |
| DLL | Wiaservc.dll |