Windows 8：如何以编程方式（使用c）读取用户文档文件夹路径？

Question

To access the files in the app directory, I am using the following line of code:

std::wstring wpath = Windows::Storage::ApplicationData::Current->LocalFolder->Path->Data();

Similar to the above code, how can I get the documents folder path? Please suggest a solution that works in Metro app.

Answer 1

I found this answer here on Stack Overflow

Because DocumentsLibrary is a virtual location representing a collection of different locations and files, it will not have a path:

Libraries, a concept introduced in Windows 7, allow users to view related user content from a single location. Because the library is a virtual location, folders that are added to or removed from a library continue to exist in their original locations as well.

In addition, the MSDN documentation for StorageFolder.Path states:

Do not rely on this property to access a folder because some folders may not have file-system paths. For example if the folder is a file group, or is backed by a URI, or was picked using the file picker, the folder is not guaranteed to have a file-system path.

but I suggest you to look at this code, search for (line 796):

case Win_Documents:
{
    return GetLibrarySaveToPath(CSIDL_MYDOCUMENTS,
                                FOLDERID_DocumentsLibrary,
                                aFile);
}

your problem seems to be resolved by this piece of code:

/*
 * Check to see if we're on Win7 and up, and if so, returns the default
 * save-to location for the Windows Library passed in through aFolderId.
 * Otherwise falls back on pre-win7 GetWindowsFolder.
 */
static nsresult
GetLibrarySaveToPath(int aFallbackFolderId, REFKNOWNFOLDERID aFolderId,
                     nsIFile** aFile)
{
    // Skip off checking for library support if the os is Vista or lower.
    DWORD dwVersion = GetVersion();
    if ((DWORD)(LOBYTE(LOWORD(dwVersion))) < 6 ||
        ((DWORD)(LOBYTE(LOWORD(dwVersion))) == 6 &&
         (DWORD)(HIBYTE(LOWORD(dwVersion))) == 0))
      return GetWindowsFolder(aFallbackFolderId, aFile);

    nsRefPtr<IShellLibrary> shellLib;
    nsRefPtr<IShellItem> savePath;
    HRESULT hr =
        SHLoadLibraryFromKnownFolder(aFolderId, STGM_READ,
                                     IID_IShellLibrary, getter_AddRefs(shellLib));

    if (shellLib &&
        SUCCEEDED(shellLib->GetDefaultSaveFolder(DSFT_DETECT, IID_IShellItem,
                                                 getter_AddRefs(savePath)))) {
        PRUnichar* str = nullptr;
        if (SUCCEEDED(savePath->GetDisplayName(SIGDN_FILESYSPATH, &str))) {
            nsAutoString path;
            path.Assign(str);
            path.AppendLiteral("\\");
            nsresult rv =
                NS_NewLocalFile(path, false, aFile);
            CoTaskMemFree(str);
            return rv;
        }
    }

    return GetWindowsFolder(aFallbackFolderId, aFile);
}