XPでIPropertyStore

xp_IPropertyStore.cpp

#define Microsoft_Office_Metadata_Handler L"{993BE281-6695-4BA5-8A2A-7AACBFAAB69E}"
#define Microsoft_Office_Thumbnail_Handler L"{C41662BB-1FA0-4CE0-8DC5-9B7F8279FF97}"
#define FilePath L"実際のパス"

#include <windows.h>
#include <ObjIdl.h>
#include <Propsys.h>
#include <Shlwapi.h>
#include <comdef.h>
#include <Propvarutil.h>

_COM_SMARTPTR_TYPEDEF(IPersistFile, __uuidof(IPersistFile));
_COM_SMARTPTR_TYPEDEF(IPropertySetStorage, __uuidof(IPropertySetStorage));
_COM_SMARTPTR_TYPEDEF(IPropertyStore, __uuidof(IPropertyStore));

int CALLBACK WinMain(
	_In_  HINSTANCE hInstance,
	_In_  HINSTANCE hPrevInstance,
	_In_  LPSTR lpCmdLine,
	_In_  int nCmdShow
	)
{

	CoInitialize(NULL);
	try {
		
		CLSID clsid;
		HRESULT hr = CLSIDFromString(Microsoft_Office_Metadata_Handler, &clsid);
		if (FAILED(hr)) _com_issue_error(hr);

		IUnknownPtr pUnk;
		hr = CoCreateInstance(clsid, NULL, CLSCTX_INPROC_SERVER, IID_PPV_ARGS(&pUnk));
		if (FAILED(hr)) _com_issue_error(hr);

		IPersistFilePtr pPersist;
		hr = pUnk.QueryInterface(IID_PPV_ARGS(&pPersist));
		hr = pPersist->Load(FilePath, STGM_READ);

		IPropertySetStoragePtr pPropSetStg;
		hr = pUnk.QueryInterface(IID_PPV_ARGS(&pPropSetStg));
		if (FAILED(hr)) _com_issue_error(hr);

		IPropertyStorePtr pPropStore;
		hr = ::PSCreatePropertyStoreFromPropertySetStorage(pPropSetStg, STGM_READWRITE, IID_PPV_ARGS(&pPropStore));
		if (FAILED(hr)) _com_issue_error(hr);

		PROPERTYKEY propKey = { FMTID_SummaryInformation, PIDSI_COMMENTS };
		PROPVARIANT propValue = { 0 };

		hr = pPropStore->GetValue(propKey, &propValue);
		if (FAILED(hr)) _com_issue_error(hr);

		PWSTR pstr;
		hr = PropVariantToStringAlloc(propValue, &pstr);
		if (FAILED(hr)) _com_issue_error(hr);
		MessageBoxW(nullptr, pstr, L"value", MB_OK);
		CoTaskMemFree(pstr);
		::PropVariantClear(&propValue);
	}
	catch (_com_error& e) {
		MessageBoxA(nullptr, (LPCSTR) e.ErrorMessage(), "err", MB_OK);
	}
	CoUninitialize();
	return 0;
}