使用 MS Graph SDK 从共享的 OneDrive 文件夹下载和上传 DriveItem

Question

我目前正在尝试执行多项任务，包括从共享的 OneDrive 文件夹中列出、上传和下载文件。可通过登录用户 OneDrive 访问此文件夹（在其根文件夹中可见）。到目前为止，列表部分运行良好，使用此代码：

string remoteDriveId = string.Empty;
private GraphServiceClient graphClient { get; set; }
// Get the root of the owners OneDrive
DriveItem ownerRoot = await this.graphClient.Drive.Root.Request().Expand("thumbnails,children($expand=thumbnails)").GetAsync();
// Select the shared folders general information
DriveItem sharedFolder = ownerRoot.Children.Where(c => c.Name == "sharedFolder").FirstOrDefault();

// Check if it is a remote folder
if(sharedFolder.Remote != null)
{
    remoteDriveId = item.RemoteItem.ParentReference.DriveId;

    // Get complete Information of the shared folder
    sharedFolder = await graphClient.Drives[remoteDriveId].Items[sharedFolder.RemoteItem.Id].Request().Expand("thumbnails,children").GetAsync();
}

很明显，我需要从与其他 OneDrive 共享的 OneDrive 中检索共享文件夹信息。我的下一部分是列出这个共享文件夹的内容，它也像这样工作得很好：

foreach (DriveItem child in sharedFolder.Children)
{
    DriveItem childItem = await graphClient.Drives[remoteDriveId].Items[child.Id].Request().Expand("thumbnails,children").GetAsync();

    if(childItem.Folder == null)
    {
         string path = Path.GetTempPath() + Guid.NewGuid();
         // Download child item to path
    }
}

我的问题从 "Download child item to path" 部分开始。在那里我想下载所有东西，那不是临时文件的文件夹。问题是 OneDrive 总是用一条错误消息来回答我的请求，即找不到文件。到目前为止我尝试的是：

using (var stream = await graphClient.Drives[remoteDriveId].Items[childItem.Id].Content.Request().GetAsync())
using (var outputStream = new System.IO.FileStream(path, System.IO.FileMode.Create))
{
    await stream.CopyToAsync(outputStream);
}

在另一个变体中，我尝试使用 childItem ParentReference 的 ID（但我认为这只会将我带到 sharedFolder 的远程 OneDrives ID）：

using (var stream = await graphClient.Drives[remoteDriveId].Items[childItem.ParentReference.Id].Content.Request().GetAsync())
using (var outputStream = new System.IO.FileStream(path, System.IO.FileMode.Create))
{
    await stream.CopyToAsync(outputStream);
}

下载文件后，我想编辑它们并将它们重新上传到共享文件夹中的不同路径。该路径是由我创建的（已经可以使用），如下所示：

DriveItem folderToCreate = new DriveItem { Name = "folderName", Folder = new Folder() };
await graphClient.Drives[remoteDriveId].Items[sharedFolder.Id].Children.Request().AddAsync(folderToCreate);

上传失败。我试过这样：

using (var stream = new System.IO.FileStream(@"C:\temp\testfile.txt", System.IO.FileMode.Open))
{
    await graphClient.Drives[remoteDriveId].Items[sharedFolder.Id].Content.Request().PutAsync<DriveItem>(stream);
}

也喜欢这样（如果它不是共享文件夹，它会起作用，因此我使用 Drive 而不是 Drives）：

using (var stream = new System.IO.FileStream(@"C:\temp\testfile.txt", System.IO.FileMode.Open))
{
    string folderPath = sharedFolder.ParentReference == null ? "" : sharedFolder.ParentReference.Path.Remove(0, 12) + "/" + Uri.EscapeUriString(sharedFolder.Name);
    var uploadPath = folderPath + "/" + uploadFileName;
    await graphClient.Drives[remoteDriveId].Root.ItemWithPath(uploadPath).Content.Request().PutAsync<DriveItem>(stream);
}

我无法使用 AddAsync 方法（就像在文件夹创建中一样），因为我不知道如何从 Stream 创建 DriveItem。

如果有人能指出正确的方向，我将不胜感激！谢谢！

Answer 1

请求：

graphClient.Drives[remoteDriveId].Items[childItem.ParentReference.Id].Content.Request().GetAsync()

对应于Download the contents of a DriveItem endpoint and is only valid if childItem.ParentReference.Id refers to a File resource，在另一种情况下它失败并出现预期的异常：

Microsoft.Graph.ServiceException: Code: itemNotFound Message: You cannot get content for a folder

因此，要从文件夹下载内容，解决方案是：

枚举文件夹下的项目：GET /drives/{drive-id}/items/{folderItem-id}/children
如果 driveItem 对应于 File 方面，则每个项目明确下载其内容：GET /drives/{drive-id}/items/{fileItem-id}/content

例子

var sharedItem = await graphClient.Drives[driveId].Items[folderItemId].Request().Expand(i => i.Children).GetAsync();
foreach (var item in sharedItem.Children)
{
    if (item.File != null)
    {
        var fileContent = await graphClient.Drives[item.ParentReference.DriveId].Items[item.Id].Content.Request()
                    .GetAsync();
        using (var fileStream = new FileStream(item.Name, FileMode.Create, System.IO.FileAccess.Write))
           fileContent.CopyTo(fileStream);

    }
}

示例 2

该示例演示了如何从 source 文件夹下载文件并将其上传到 target 文件夹：

  var sourceDriveId = "--source drive id goes here--";
  var sourceItemFolderId = "--source folder id goes here--";
  var targetDriveId = "--target drive id goes here--";
  var targetItemFolderId = "--target folder id goes here--";

 var sourceFolder = await graphClient.Drives[sourceDriveId].Items[sourceItemFolderId].Request().Expand(i => i.Children).GetAsync();
 foreach (var item in sourceFolder.Children)
 {
    if (item.File != null)
    {
        //1. download a file as a stream
        var fileContent = await graphClient.Drives[item.ParentReference.DriveId].Items[item.Id].Content.Request()
            .GetAsync();
        //save it into file 
        //using (var fileStream = new FileStream(item.Name, FileMode.Create, System.IO.FileAccess.Write))
        //    fileContent.CopyTo(fileStream);


        //2.Upload file into target folder
        await graphClient.Drives[targetDriveId]
             .Items[targetItemFolderId]
             .ItemWithPath(item.Name)
             .Content
             .Request()
             .PutAsync<DriveItem>(fileContent);

    }
 }

而不是 downloading/uploading 文件内容，我认为你真正想要的是 DriveItem copy or move 操作。假设有一些文件需要从一个 (source) 文件夹 copied 到另一个 (target) 文件夹，那么下面的例子演示了如何完成它：

  var sourceDriveId = "--source drive id goes here--";
  var sourceItemFolderId = "--source folder id goes here--";
  var targetDriveId = "--target drive id goes here--";
  var targetItemFolderId = "--target folder id goes here--";

  var sourceFolder = await graphClient.Drives[sourceDriveId].Items[sourceItemFolderId].Request().Expand(i => i.Children).GetAsync();
  foreach (var item in sourceFolder.Children)
  {
      if (item.File != null)
      {
          var parentReference = new ItemReference
          {
               DriveId = targetDriveId,
               Id = targetItemFolderId
          };
          await graphClient.Drives[sourceDriveId].Items[item.Id]
              .Copy(item.Name, parentReference)
              .Request()
              .PostAsync();
         }
      }
  }

使用 MS Graph SDK 从共享的 OneDrive 文件夹下载和上传 DriveItem

Download and upload DriveItem from shared OneDrive Folder with MS Graph SDK

c#

onedrive

microsoft-graph-api