如何在新版Microsoft.Graph中添加Request Adapter？.NET C#适配指导

新版Microsoft Graph SDK（v5及以上）彻底重构了认证和请求适配逻辑，旧版的DelegateAuthenticationProvider已被移除，改用Azure Identity库的凭证类处理认证，同时GraphServiceClient的构造方式也发生了变化。以下是针对你旧代码的完整适配方案：

核心变化说明 #

• 弃用旧版ConfidentialClientApplication，改用Azure.Identity.ClientSecretCredential管理服务主体认证
• 无需手动实现Token注入逻辑，SDK通过BaseBearerTokenAuthenticationProvider自动处理
• GraphServiceClient支持直接传入TokenCredential实例，内部自动构建RequestAdapter

完整适配代码 #

using Azure.Identity;
using Microsoft.Graph;
using Microsoft.Extensions.Configuration;

private GraphServiceClient CreateGraphServiceClient()
{
    var scopes = new[] { "https://graph.microsoft.com/.default" };
    var tenantId = _configuration["Microsoft-Graph:tenantId"];
    var clientId = _configuration["Microsoft-Graph:clientId"];
    var clientSecret = _configuration["Microsoft-Graph:clientSecretValue"];

    // 初始化服务主体凭证，替代旧版的ConfidentialClientApplication
    var credential = new ClientSecretCredential(
        tenantId,
        clientId,
        clientSecret);

    // 直接传入凭证和作用域，SDK自动处理RequestAdapter和认证逻辑
    var graphClient = new GraphServiceClient(credential, scopes);

    return graphClient;
}

手动构建RequestAdapter的场景（自定义HttpClient等） #

如果需要自定义HttpClient或精细控制RequestAdapter，可使用以下方式：

using Azure.Identity;
using Microsoft.Graph;
using System.Net.Http;

private GraphServiceClient CreateGraphServiceClientWithCustomAdapter()
{
    var scopes = new[] { "https://graph.microsoft.com/.default" };
    var tenantId = _configuration["Microsoft-Graph:tenantId"];
    var clientId = _configuration["Microsoft-Graph:clientId"];
    var clientSecret = _configuration["Microsoft-Graph:clientSecretValue"];

    var credential = new ClientSecretCredential(tenantId, clientId, clientSecret);
    var httpClient = new HttpClient(); // 可自定义超时、代理等HttpClient配置

    // 构建认证提供者
    var authProvider = new BaseBearerTokenAuthenticationProvider(credential);

    // 创建RequestAdapter实例
    var requestAdapter = new HttpClientRequestAdapter(authProvider, httpClient: httpClient);
    requestAdapter.BaseUrl = "https://graph.microsoft.com/v1.0"; // 指定Graph API版本

    // 使用RequestAdapter初始化GraphServiceClient
    var graphClient = new GraphServiceClient(requestAdapter);

    return graphClient;
}

注意事项 #

• 必须安装NuGet包：Microsoft.Graph（最新稳定版）和Azure.Identity，旧版Microsoft.Graph.Auth已被弃用，请勿使用
• 修正你新版代码中的拼写错误：https://graph.micorsoft.com/.default → https://graph.microsoft.com/.default
• 确保服务主体已获得对应的Graph API权限（且已完成管理员同意）

内容的提问来源于stack exchange，提问作者Robin Singh