如何使用Microsoft Graph SDK通过用户名和密码生成GraphClient？

using Microsoft.Graph;
using System.Net.Http.Headers;

GraphServiceClient graphClient = new GraphServiceClient(new UsernamePasswordProvider(authenticationProvider));

public class UsernamePasswordProvider : IAuthenticationProvider
{
    private string username;
    private string password;

    public UsernamePasswordProvider(string username, string password)
    {
        this.username = username;
        this.password = password;
    }

    public async Task AuthenticateRequestAsync(HttpRequestMessage request)
    {
        request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", await GetAccessTokenAsync());
    }

    private async Task<string> GetAccessTokenAsync()
    {
        // 在此处实现获取访问令牌的逻辑，可以使用Microsoft.Identity.Client等库来获取令牌
        // 这里省略获取令牌的具体实现
        string accessToken = await GetAccessTokenFromIdentityProviderAsync();

        return accessToken;
    }
}

var user = await graphClient.Me.Request().GetAsync();
Console.WriteLine($"User: {user.DisplayName}");