问来自Web API的Access Graph API引发未经授权的错误v2.0

EN

ConfidentialClientApplication cl = new ConfidentialClientApplication(
    clientId,
    "https://login.microsoftonline.com/common/v2.0/token",
    "https://localhost:44321/",
    new ClientCredential(appKey),
    new TokenCache(), null);

AuthenticationResult authResult = await cl.AcquireTokenForClientAsync(new string[] { "https://graph.microsoft.com/.default" });

string oid = ClaimsPrincipal.Current.FindFirst("http://schemas.microsoft.com/identity/claims/objectidentifier").Value;

client = new HttpClient();
request = new HttpRequestMessage(HttpMethod.Get, "https://graph.microsoft.com/v1.0/users/" + oid);
request.Headers.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Bearer", authResult.AccessToken);

response = await client.SendAsync(request);