问如何使用Microsoft Graph API C# SDK将文件上传到SharePoint库文件夹？

EN

try
{
    using var stream = new MemoryStream(contentBytes);

    // Retrieve the folder item.
    var items = await this._graphClient.Sites["siteId"].Lists["listId"].Items
        .Request()
        .GetAsync();

    // I happened to know the folder name in advance, so that is what I used to retrieve the folder item from Items collection.
    // I could not find how to query the Graph to get just the folder instead of all the items. Hopefully I will find it and update the code.
    var folderItem = items.FirstOrDefault(i => i.WebUrl.Contains($"{path}") && i.ContentType.Name == "Folder");

    // you must create a DriveItem, not a ListItem object. It is important to set the the File property.
    var listItem = new DriveItem
    {
        Name = fileName,
        File = new Microsoft.Graph.File(),
        AdditionalData = new Dictionary<string, object>()
                {
                    { "@microsoft.graph.conflictBehavior", "replace" }
                },

    };

    listItem = await this._graphClient.Sites["siteId"].Lists["listId"].Items[folderItem.Id].DriveItem.Children
        .Request()
        .AddAsync(listItem);

    // I needed the drive Id here. it is in the Drives properties of the site. It corresponds to the drive associated to the library.
    var uploadSession = await this._graphClient.Sites["siteId"].Drives["driveId"]
        .Items[listItem.Id]
        .CreateUploadSession()
        .Request()
        .PostAsync();

    var largeFileUploadTask = new LargeFileUploadTask<DriveItem>(uploadSession, stream);

    UploadResult<DriveItem> uploadResult = await largeFileUploadTask.UploadAsync();

    return uploadResult;
}
catch (ServiceException e)
{
    Log.Error(e);
    throw;
}

var siteQueryOptions = new List<QueryOption>()
{
    new QueryOption("expand", "drives")
};

var site = await this._graphClient.Sites.GetByPath(siteRelativeUrl, hostName)
    .Request(siteQueryOptions)
    .GetAsync();

string driveId = site.Drives.FirstOrDefault(d => d.WebUrl.EndsWith(workingDocumentsLibName, StringComparison.InvariantCultureIgnoreCase))?.Id;