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

使用Microsoft Graph API C# SDK将文件上传到SharePoint库文件夹的步骤如下：

首先，确保已安装并引用了Microsoft Graph API C# SDK。可以通过NuGet包管理器或手动下载并添加引用。
创建一个Microsoft Graph API的客户端实例，可以使用以下代码示例：

using Microsoft.Graph;
using Microsoft.Identity.Client;

// 创建一个GraphServiceClient实例
GraphServiceClient graphClient = new GraphServiceClient(new DelegateAuthenticationProvider(async (requestMessage) =>
{
    // 在此处进行身份验证，获取访问令牌
    var scopes = new[] { "https://graph.microsoft.com/.default" };
    var confidentialClientApplication = ConfidentialClientApplicationBuilder
        .Create("YourClientId")
        .WithClientSecret("YourClientSecret")
        .WithAuthority("https://login.microsoftonline.com/YourTenantId")
        .Build();

    var authResult = await confidentialClientApplication.AcquireTokenForClient(scopes).ExecuteAsync();
    requestMessage.Headers.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Bearer", authResult.AccessToken);
}));

使用以下代码示例将文件上传到SharePoint库文件夹：

using System.IO;

// 上传文件到SharePoint库文件夹
var driveId = "YourDriveId";
var folderId = "YourFolderId";
var filePath = "YourFilePath";

// 读取文件内容
var fileStream = new FileStream(filePath, FileMode.Open);
var uploadSession = await graphClient.Sites["root"].Drives[driveId].Items[folderId].ItemWithPath(Path.GetFileName(filePath)).CreateUploadSession().Request().PostAsync();

// 上传文件内容
var maxChunkSize = 320 * 1024; // 设置每个分块的最大大小
var provider = new ChunkedUploadProvider(uploadSession, graphClient, fileStream, maxChunkSize);
var chunkRequests = provider.GetUploadChunkRequests();
var exceptions = new List<Exception>();

foreach (var request in chunkRequests)
{
    var result = await provider.GetChunkRequestResponseAsync(request, exceptions);

    if (result.UploadSucceeded)
    {
        // 分块上传成功
    }
}

// 完成上传
var uploadResult = await provider.GetUploadResultAsync();
if (uploadResult.UploadSucceeded)
{
    // 文件上传成功
}

以上代码示例中，需要替换以下参数：