LINQ to Outlook Data

This article illustrates using LINQ to access tables within the Outlook via the CData ADO.NET Data Provider for Outlook. To achieve this, we will use LINQ to Entity Framework, which facilitates the generation of connections and can be seamlessly employed with any CData ADO.NET Data Providers to access data through LINQ.

See the help documentation for a guide to setting up an EF 6 project to use the provider.

1. In a new project in Visual Studio, right-click on the project and choose to add a new item. Add an ADO.NET Entity Data Model.
2. Choose EF Designer from Database and click Next.
3. Add a new Data Connection, and change your data source type to "CData Outlook Data Source".

4. Enter your data source connection information.

   Using OAuth Authentication

   Microsoft Graph API uses OAuth 2.0 for authentication. You must register an application in the Microsoft Azure Portal to obtain OAuth credentials (Client ID and Client Secret).

   Obtaining OAuth Credentials

   1. Log in to the Azure Portal.
   2. Navigate to Azure Active Directory > App registrations.
   3. Click New registration to create a new application.
   4. Enter an application name and select the appropriate account types.
   5. Set the Redirect URI to your application's callback URL (e.g., http://localhost:33333 for desktop apps).
   6. Click Register to create the application.
   7. On the application overview page, copy the Application (client) ID - this is your OAuthClientId.
   8. Navigate to Certificates & secrets and create a new client secret.
   9. Copy the client secret value - this is your OAuthClientSecret.
   10. Navigate to API permissions and add the required Microsoft Graph API permissions:
       • Mail.Read - For accessing email messages
       • Contacts.Read - For accessing contacts
       • Calendars.Read - For accessing calendar events
       • Tasks.Read - For accessing To Do tasks
       • offline_access - For obtaining refresh tokens
   11. Click Grant admin consent to grant these permissions.

   Connecting with OAuth

   After setting the following connection properties, you are ready to connect:

   • AuthScheme: Set this to OAuth.
   • InitiateOAuth: Set this to GETANDREFRESH. The CData API Profile for Outlook will automatically walk through the OAuth process in order to obtain the access token.
   • OAuthClientId: Set this to the Application (client) ID from Azure Portal.
   • OAuthClientSecret: Set this to the client secret value from Azure Portal.
   • TenantId: Set this to your Azure AD tenant identifier (GUID or domain name like 'contoso.onmicrosoft.com').
   • CallbackURL: Set this to the Redirect URI you specified in your app registration (e.g., http://localhost:33333 for desktop apps).

   Example connection string

   Profile=C:\profiles\Outlook.apip;AuthScheme=OAuth;InitiateOAuth=GETANDREFRESH;OAuthClientId=your_client_id;OAuthClientSecret=your_client_secret;TenantId=your_tenant_id;CallbackUrl=http://localhost:33333;
   

   Below is a typical connection string:

   Profile=C:\profiles\Outlook.apip;AuthScheme=OAuth;InitiateOAuth=GETANDREFRESH;OAuthClientId=your_client_id;OAuthClientSecret=your_client_secret;TenantId=your_tenant_id;CallbackUrl=http://localhost:33333;


5. If saving your entity connection to App.Config, set an entity name. In this example we are setting APIEntities as our entity connection in App.Config.
6. Enter a model name and select any tables or views you would like to include in the model.

Using the entity you created, you can now perform select commands. For example:

APIEntities context = new APIEntities();

var calendargroupcalendarsQuery = from calendargroupcalendars in context.CalendarGroupCalendars
  select calendargroupcalendars;

foreach (var result in calendargroupcalendarsQuery) {
  Console.WriteLine("{0} {1} ", result.Id, result.);
}

See "LINQ and Entity Framework" chapter in the help documentation for example queries of the supported LINQ.