使用 IShellDispatch 的 C++ 解压缩失败

Question

所以我有一个非常简单的工作要做:解压缩一个 zip 文件。我以为我会在 5 秒内在线找到一个简单的解决方案，但我仍在苦苦挣扎。

我显然已经阅读了这些帖子:

• Simple way to unzip a .zip file using zlib
• Simplest way to unpack ZIP from C++?

但答案建议使用zlib 和libzip 或miniz。我相信这些方法效果很好。然而，在现有的 VS2013 解决方案中尝试应用这种方法似乎并不简单。

然后我遇到了这个简单的解决方案，ref1 , ref2 ，利用 IShellDispatch object

我赶紧去实现它:

bool DecompressZIP(_In_ const wpath& pathFile, _In_ const wpath& pathDstDir)
{
    BSTR source = _bstr_t(pathFile.string().c_str());
    BSTR dest = _bstr_t(pathDstDir.string().c_str());

    HRESULT hResult = S_FALSE;
    IShellDispatch *pIShellDispatch = NULL;
    Folder *pToFolder = NULL;
    VARIANT variantDir, variantFile, variantOpt;

    CoInitialize(NULL);

    hResult = CoCreateInstance(CLSID_Shell, NULL, CLSCTX_INPROC_SERVER,
        IID_IShellDispatch, (void **)&pIShellDispatch);

    if (SUCCEEDED(hResult) && NULL != pIShellDispatch)
    {
        VariantInit(&variantDir);
        variantDir.vt = VT_BSTR;
        variantDir.bstrVal = dest;
        hResult = pIShellDispatch->NameSpace(variantDir, &pToFolder);

        if (SUCCEEDED(hResult) && NULL != pToFolder)
        {
            Folder *pFromFolder = NULL;
            VariantInit(&variantFile);
            variantFile.vt = VT_BSTR;
            variantFile.bstrVal = source;
            hResult = pIShellDispatch->NameSpace(variantFile, &pFromFolder);

            if (SUCCEEDED(hResult) && NULL != pFromFolder)
            {
                FolderItems *fi = NULL;
                pFromFolder->Items(&fi);

                VariantInit(&variantOpt);
                variantOpt.vt = VT_I4;
                variantOpt.lVal = FOF_NO_UI;

                VARIANT newV;
                VariantInit(&newV);
                newV.vt = VT_DISPATCH;
                newV.pdispVal = fi;
                hResult = pToFolder->CopyHere(newV, variantOpt);
                Sleep(1000);
                pFromFolder->Release();
                pToFolder->Release();
            }
        }
        pIShellDispatch->Release();
    }

    CoUninitialize();

    return true;
}

但它不起作用!

行:hResult = pIShellDispatch->NameSpace(variantFile, &pFromFolder);始终导致 pFromFolder == NULL

• hResult 为 S_FALSE
• SUCCEEDED(hResult) 为真
• GetLastError 为 0

问题

我做错了什么？

Answer 1

bool CUnZip::Unzip2Folder(BSTR lpZipFile, BSTR lpFolder)
{
IShellDispatch *pISD;
Folder  *pZippedFile = 0L;
Folder  *pDestination = 0L;

long FilesCount = 0;
IDispatch* pItem = 0L;
FolderItems *pFilesInside = 0L;

VARIANT Options, OutFolder, InZipFile, Item;
CoInitialize(NULL);
__try{
    if (CoCreateInstance(CLSID_Shell, NULL, CLSCTX_INPROC_SERVER, IID_IShellDispatch, (void **)&pISD) != S_OK)
        return 1;

    InZipFile.vt = VT_BSTR;
    InZipFile.bstrVal = lpZipFile;
    pISD->NameSpace(InZipFile, &pZippedFile);
    if (!pZippedFile)
    {
        pISD->Release();
        return 1;
    }

    OutFolder.vt = VT_BSTR;
    OutFolder.bstrVal = lpFolder;
    pISD->NameSpace(OutFolder, &pDestination);
    if (!pDestination)
    {
        pZippedFile->Release();
        pISD->Release();
        return 1;
    }

    pZippedFile->Items(&pFilesInside);
    if (!pFilesInside)
    {
        pDestination->Release();
        pZippedFile->Release();
        pISD->Release();
        return 1;
    }

    pFilesInside->get_Count(&FilesCount);
    if (FilesCount < 1)
    {
        pFilesInside->Release();
        pDestination->Release();
        pZippedFile->Release();
        pISD->Release();
        return 0;
    }

    pFilesInside->QueryInterface(IID_IDispatch, (void**)&pItem);

    Item.vt = VT_DISPATCH;
    Item.pdispVal = pItem;

    Options.vt = VT_I4;
    Options.lVal = 1024 | 512 | 16 | 4;//http://msdn.microsoft.com/en-us/library/bb787866(VS.85).aspx

    bool retval = pDestination->CopyHere(Item, Options) == S_OK;

    pItem->Release(); pItem = 0L;
    pFilesInside->Release(); pFilesInside = 0L;
    pDestination->Release(); pDestination = 0L;
    pZippedFile->Release(); pZippedFile = 0L;
    pISD->Release(); pISD = 0L;

    return retval;

}
__finally
{
    CoUninitialize();
}

来源:https://social.msdn.microsoft.com/Forums/vstudio/en-US/45668d18-2840-4887-87e1-4085201f4103/visual-c-to-unzip-a-zip-file-to-a-specific-directory?forum=vclanguage

在主要情况下，您调用:

CUnZip * Z = new CUnZip();
        BSTR bstrFile = strFileName.AllocSysString();
        BSTR bstrPath = m_strPathName.AllocSysString();
        Z->Unzip2Folder(bstrFile, bstrPath);
        delete Z;
        Z = NULL;