Question

我正在编写一个程序，允许用户将文件上传到他们的Google云端硬盘帐户。我有上传部分工作，我正在使用OAuth2。我目前遇到的问题是从用户云端硬盘帐户中获取文件夹列表。

我发现了一些应该使用.setUserCredentials方法执行此操作的代码，但它不起作用：

DocumentsService service1 = new DocumentsService("project");            
        service1.setUserCredentials("user","pass");

        FolderQuery query1 = new FolderQuery();

        // Make a request to the API and get all documents.
        DocumentsFeed feed = service1.Query(query1);

        // Iterate through all of the documents returned
        foreach (DocumentEntry entry in feed.Entries)
        {
            var blech = entry.Title.Text;
        }

没有返回任何内容。理想情况下，我想使用OAuth2来执行此操作。我一直在尝试使用以下代码，尝试设置身份验证令牌，但我总是被拒绝访问：

String CLIENT_ID = "clientid";
String CLIENT_SECRET = "secretid";

var docprovider = new NativeApplicationClient(GoogleAuthenticationServer.Description, CLIENT_ID, CLIENT_SECRET);
var docstate = GetDocAuthentication(docprovider);

DocumentsService service1 = new DocumentsService("project");

service1.SetAuthenticationToken(docstate.RefreshToken);
FolderQuery query1 = new FolderQuery();

DocumentsFeed feed = service1.Query(query1); //get error here

        // Iterate through all of the documents returned
        foreach (DocumentEntry entry in feed.Entries)
        {
            // Print the title of this document to the screen
            var blech = entry.Title.Text;
        }

...

    private static IAuthorizationState GetDocAuthentication(NativeApplicationClient client)
    {
        const string STORAGE = "storagestring";
        const string KEY = "keystring";
        string scope = "https://docs.google.com/feeds/default/private/full/-/folder";            
        // Check if there is a cached refresh token available.
        IAuthorizationState state = AuthorizationMgr.GetCachedRefreshToken(STORAGE, KEY);
        if (state != null)
        {
            try
            {
                client.RefreshToken(state);
                return state; // Yes - we are done.
            }
            catch (DotNetOpenAuth.Messaging.ProtocolException ex)
            {

            }
        }

        // Retrieve the authorization from the user.
        state = AuthorizationMgr.RequestNativeAuthorization(client, scope);
        AuthorizationMgr.SetCachedRefreshToken(STORAGE, KEY, state);
        return state;
    }

具体来说，我得到“执行请求失败：https://docs.google.com/feeds/default/private/full/-/folder - 远程服务器返回错误：（401）未经授权”。

我也试过了：

var docauth = new OAuth2Authenticator<NativeApplicationClient>(docprovider, GetDocAuthentication);
DocumentsService service1 = new DocumentsService("project");
service1.SetAuthenticationToken(docauth.State.AccessToken);

但“State”始终为null，因此我得到一个null对象错误。我做错了什么，这是怎么做到的？

Answer 1

您应该使用Drive SDK，而不是文档列表API，它允许您list folders。如果要列出根目录，可以使用“root”作为folderId。

Answer 2

private IEnumerable<DocumentEntry> GetFolders(string id) {
    if (IsLogged) {
        var query = new FolderQuery(id)
        {
            ShowFolders = true
        };

        var feed = GoogleDocumentsService.Query(query);

        return feed.Entries.Cast<DocumentEntry>().Where(x => x.IsFolder).OrderBy(x => x.Title.Text);
    }

    return null;
}

    ...
var rootFolders = GetFolders("root");
if (rootFolders != null){
    foreach(var folder in rootFolders){
        var subFolders = GetFolders(folder.ResourceId);
        ...
    }
}

其中GoogleDocumentsService是DocumentsService的实例，IsLogged是成功记录的标记。

Answer 3

我有这样的方法来获取谷歌驱动器中的文件夹列表

  FilesResource.ListRequest filelist= service.Files.List();
  filelist.Execute().Items.ToList().Where(x => x.MimeType == "application/vnd.google-apps.folder").ToList()

Answer 4

我实际上实现了适用于.NET的GDrive SDK v3版本，还需要搜索文件夹。

我更喜欢唯一地请求所有文件夹，而不是获取所有文件，然后执行LinQ查询以仅保留文件夹。

这是我的实现方式

private async Task<bool> FolderExistsAsync(string folderName)
{
    var response = await GetAllFoldersAsync();
    return response.Files
                   .Where(x => x.Name.ToLower() == folderName.ToLower())
                   .Any();
}

private async Task<Google.Apis.Drive.v3.Data.FileList> GetAllFoldersAsync()
{
    var request = _service.Files.List();
    request.Q = "mimeType = 'application/vnd.google-apps.folder'";
    var response = await request.ExecuteAsync();
    return response;
}

您也可以通过以下方式在Q上请求名称：

request.Q = $"mimeType = 'application/vnd.google-apps.folder' and name = '{folderName}'";

这将导致并简化（避免null检查）：

private async Task<bool> FolderExistsAsync(string folderName)
{
    var response = await GetDesiredFolder(folderName);
    return response.Files.Any();
}

private async Task<FileList> GetDesiredFolder(string folderName)
{
    var request = _service.Files.List();
    request.Q = $"mimeType = 'application/vnd.google-apps.folder' and name = '{folderName}'";
    var response = await request.ExecuteAsync();
    return response;
}

C＃谷歌驱动器sdk。如何获取谷歌驱动器文件夹列表？

4 个答案: