如何在 C# Web 表单中使用带有委托权限的 microsoft graph api 读取电子邮件附件

Question

我是 Microsoft Graph API 的新手。我的要求是读取所有电子邮件附件并将它们插入 SQL 数据库。我的客户只允许委托权限来实现此要求。我遵循下面提到的代码，但它没有向我显示任何错误或任何结果。

var scopes = new[] { "https://graph.microsoft.com/.default" };
var tenantId = "tenant_name.onmicrosoft.com";
var clientId = "azure_ad_appid";
var clientSecret = "client_secret";
var clientSecretCredential = new ClientSecretCredential(
    tenantId, clientId, clientSecret);
var graphClient = new GraphServiceClient(clientSecretCredential, scopes);
var inboxMessages = await graphClient
                    .Users["[email protected]"]
                    .MailFolders["inbox"]
                    .Messages
                    .Request()
                    .Expand("attachments")
                    .Top(20)
                    .GetAsync();

任何人，请帮我解决这个问题。微软将在本月底禁用基本身份验证，所以我必须在此之前实现这一点。

提前致谢。

Answer 1

我尝试在我的环境中重现相同的结果并得到以下结果：

我运行了与您相同的代码，并得到了相同的结果，没有输出或错误，如下所示：

using Azure.Identity;
using Microsoft.Graph;

var scopes = new[] { "https://graph.microsoft.com/.default" };
var tenantId = "tenant_name.onmicrosoft.com";
var clientId = "azure_ad_appid";
var clientSecret = "client_secret";
var clientSecretCredential = new ClientSecretCredential(
    tenantId, clientId, clientSecret);
var graphClient = new GraphServiceClient(clientSecretCredential, scopes);
var inboxMessages = await graphClient
                    .Users["[email protected]"]
                    .MailFolders["inbox"]
                    .Messages
                    .Request()
                    .Expand("attachments")
                    .Top(20)
                    .GetAsync();

回复：

正如我在评论中提到的，您需要使用像授权码这样的交互流程来获得

Delegated

权限。

我通过使用 Delegated 权限的

Graph Explorer

成功获得结果，如下所示：

GET https://graph.microsoft.com/v1.0/me/messages/<messageID>?$expand=attachments

回复：

您可以在此处获取示例 C# 代码片段：

GraphServiceClient graphClient = new GraphServiceClient( authProvider );
var message = await graphClient.Me.Messages["messageID"]
.Request()
.Expand("attachments")
.GetAsync();

完整示例代码：

using Azure.Identity;
using Microsoft.Graph;

var scopes = new[] { "https://graph.microsoft.com/.default" };
var tenantId = "tenant_name.onmicrosoft.com";
var clientId = "azure_ad_appid";
var clientSecret = "client_secret";
var authorizationCode = "code that you got in below request";

// using Azure.Identity;
var options = new TokenCredentialOptions
{
    AuthorityHost = AzureAuthorityHosts.AzurePublicCloud
};

// https://learn.microsoft.com/dotnet/api/azure.identity.authorizationcodecredential
var authCodeCredential = new AuthorizationCodeCredential(
    tenantId, clientId, clientSecret, authorizationCode, options);

var graphClient = new GraphServiceClient(authCodeCredential, scopes);

var message = await graphClient.Me.Messages["messageID"]
    .Request()
    .Expand("attachments")
    .GetAsync();

要获取授权

code

值，您可以使用以下请求：

https://login.microsoftonline.com/<tenantID>/oauth2/v2.0/authorize
?client_id=<appID>
&response_type=code
&redirect_uri=https://jwt.ms
&response_mode=query
&scope=https://graph.microsoft.com/.default
&state=12345

当我在浏览器中运行上述请求时。我得到了

code

以及 重定向 URI，如下所示：

Answer 2

我以不同的方式实现了这一点。所以我发布我的代码，这样它可能会对某人有所帮助。

var options = new TokenCredentialOptions
{
    AuthorityHost = AzureAuthorityHosts.AzurePublicCloud
};

var userNameCredential = new UsernamePasswordCredential(mailboxUser, mailboxPass, tenantId, clientId, options);
var graphClient = new GraphServiceClient(userNameCredential, scopes);
var graphResult = graphClient.Users[mailboxUser].MailFolders["inbox"]
                        .Messages
                        .Request()
                        .Expand("attachments").GetAsync().Result;

var attachmentMessage = graphResult.Where(x => x.HasAttachments == true);
foreach (var message in attachmentMessage)
{
    var mailReceiveDate = Convert.ToDateTime(message.ReceivedDateTime.ToString());
   string fromEmail = message.From.EmailAddress.Address.ToString();
  string mailSubject = message.Subject;

 if (attachment.ODataType == "#microsoft.graph.itemAttachment")
  {
    var attachmentRequest = graphClient.Me.MailFolders.Inbox.Messages[message.Id]
                          .Attachments[attachment.Id]
                          .Request()
                          .Expand("microsoft.graph.itemattachment/item")
                          .GetAsync();

     var itemAttachment = (ItemAttachment)attachmentRequest.Result;
     var itemMessage = (Message)itemAttachment.Item;
   }
 }

这是我实施的解决方案。