From Tracker Software PDF SDK
Sets value in the Info dictionary of the structure document.
HRESULT SetInfoVar([in] LPWSTR sKey, [in] IPXS_PDFVariant* pValue);
- [in] Key that needs to be set with the given value.
- [in] Pointer to IPXS_PDFVariant containing the value that needs to be set.
Returns S_OK if operation was successful or error code in other cases.