如何在.NET Core3.1中将Microsoft Graph客户端服务添加为MediatR服务？

using MediatR;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Graph;
using Microsoft.Identity.Client;

public class Startup
{
    public void ConfigureServices(IServiceCollection services)
    {
        // 添加MediatR服务
        services.AddMediatR(typeof(Startup));

        // 添加Microsoft Graph客户端服务
        services.AddSingleton<IGraphServiceClient>(provider =>
        {
            var clientId = "YourClientId";
            var clientSecret = "YourClientSecret";
            var tenantId = "YourTenantId";
            var authority = $"https://login.microsoftonline.com/{tenantId}";

            var confidentialClientApplication = ConfidentialClientApplicationBuilder
                .Create(clientId)
                .WithClientSecret(clientSecret)
                .WithAuthority(authority)
                .Build();

            var authProvider = new ClientCredentialProvider(confidentialClientApplication);

            return new GraphServiceClient(authProvider);
        });
    }
}

using MediatR;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Graph;

public class MyController : ControllerBase
{
    private readonly IGraphServiceClient _graphServiceClient;

    public MyController(IGraphServiceClient graphServiceClient)
    {
        _graphServiceClient = graphServiceClient;
    }

    public async Task<IActionResult> MyAction()
    {
        // 使用IGraphServiceClient调用Microsoft Graph的API
        var users = await _graphServiceClient.Users.Request().GetAsync();

        // 处理返回结果
        // ...

        return Ok();
    }
}