When working with Microsoft 365 data, such as emails, calendars, contacts or tasks, it is not always necessary to retrieve all items. It’s also useful to be able to filter, sort and retrieve specific data properties in your email applications. For example, filtering messages by sender, sorting calendar events by date or fetching only a few fields can help keep your app fast.

That’s where OData queries come in. Microsoft Graph supports OData to help developers filter, sort, and select data directly on the server before it’s even sent to your app. The result is a faster performance, smaller payloads, and more responsive applications.

Aspose.Email for .NET makes this process easy with its [ODataQueryBuilder][2] class. In this article, we’ll explore how it works and how you can use it to build dynamic, powerful Microsoft Graph queries in C#.

Why Use OData Queries?

The Microsoft Graph API offers extensive features but can be complex when building queries manually. OData parameters enable server-side filtering, sorting, paging, and property selection, which minimizes client-side processing. This approach enhances efficiency by reducing data transfer and accelerating response times, making your applications faster and more scalable.

With OData support, you can now:

  • Filter messages, contacts, or events using custom conditions.
  • Sort data via OrderBy for ascending or descending order.
  • Select only the needed properties to minimize payload size.
  • Implement paging using Top and Skip, ideal for large mailboxes.
  • Expand related entities (e.g., attachments) with Expand.
  • Count and search datasets for faster access.

These capabilities are accessible and type-safe through the new [ODataQueryBuilder][2] class.

Your .NET Component to Build Microsoft Graph Queries in C#

Aspose.Email for .NET is a powerful API for processing emails that enables developers to work directly with Microsoft 365, Exchange and Outlook data in C#. It supports the reading and writing of popular email formats, such as MSG, EML, PST and MBOX, and integrates with various protocols and services, including the Microsoft Graph API.

Using the built-in [ODataQueryBuilder][2], you can build dynamic and type-safe OData queries in C#. This makes it easy to filter, sort, and retrieve specific mailbox data - messages, contacts, or calendar events without writing complex query strings manually.

By offloading query logic to the Microsoft Graph server, Aspose.Email for .NET helps developers create faster, more efficient, and scalable applications that interact with Microsoft 365 data.

To get started, install the Aspose.Email NuGet package in your .NET project:

Install-Package Aspose.Email

This package includes all the necessary classes satisfy your needs.

Introducing the ODataQueryBuilder Class

The [Aspose.Email.Clients.Graph.ODataQueryBuilder][2] class is built to simplify how you write Graph queries. You can use it with several Graph client methods, including:

  • ListFolders
  • ListMessages
  • ListContacts
  • ListCalendarItems
  • ListAttachments
  • ListCategories
  • ListOverrides
  • ListRules
  • ListTaskLists
  • ListTasks
  • ListNotebooks

Each supports an optional ODataQueryBuilder parameter for advanced filtering, sorting, paging, and selection, right inside your Graph requests.

Practical Example: Filter and Sort Mailbox Data

The code sample below demonstrates both basic and advanced query scenarios. It showcases folder sorting and advanced message filtering, illustrating OData parameters for order, criteria, paging, selected fields, and related entities expansion.

var accessParameters = Settings.User1;
var provider = new AzureConfidentialTokenProvider(
    accessParameters.TenantId,
    accessParameters.ClientId,
    accessParameters.ClientSecret);

var client = GraphClient.GetClient(provider, accessParameters.TenantId);
client.Resource = Aspose.Email.Clients.Graph.ResourceType.Users;
client.ResourceId = accessParameters.Username;
client.EndPoint = "https://graph.microsoft.com";

// List folders sorted by name
var builder = new ODataQueryBuilder { OrderBy = "name asc" };
var folders = client.ListFolders(builder);
foreach (var folder in folders)
    Console.WriteLine(folder.DisplayName);

// Advanced message filtering
var folderId = folders.Find(x => x.DisplayName == "Inbox").ItemId;
builder = new ODataQueryBuilder {
    Filter = "startswith(name,'A')",
    OrderBy = "name asc",
    Top = 10,
    Skip = 5,
    Select = new[] { "name", "age" },
    Expand = new[] { "children", "parents" },
    Count = true,
    Search = "\"John Doe\"",
    Format = "json"
};
var msgs = client.ListMessages(folderId, builder);
foreach (var msg in msgs)
    Console.WriteLine(msg.Subject);

Real-World Scenarios

Consider some practical situations where the [ODataQueryBuilder][2] can be applied to enhance working with Microsoft Graph data in your .NET applications:

1. UI Folder Lists
Sort folders alphabetically [OrderBy][3] = "name asc" for a clean user interface.

2. Custom Filtering
Use [Filter][4] to find messages from specific senders or with certain subjects.

3. Paging Large Mailboxes
Combine [Top][5] and [Skip][6] to break down huge mailboxes into manageable results.

4. Select Specific Properties
Fetch only the fields you need with [Select][7] to minimize payload and speed up performance.

5. Include Related Data
Use [Expand][8] to include attachments, categories, or threads in a single query.

Tips for Effective OData Utilization

  • Confirm that your GraphClient accurately specifies Resource, ResourceId, and EndPoint.
  • Choose an appropriate authentication provider, such as [AzureConfidentialTokenProvider][13].
  • Combine [Filter][4], [Select][7], [OrderBy][3], and [Top][5] for optimal queries.
  • Leverage [Count][14] for total item numbers without loading all data.
  • Prepare for paging logic to handle large datasets efficiently.

Conclusion

In this article, we have learned how to use the [ODataQueryBuilder][2] class of the Aspose.Email for .NET library for building and executing Microsoft Graph queries. Instead of composing OData syntax manually, you can now create type-safe, dynamic, and readable queries directly in your C# code. The introduction of OData query support in Aspose.Email for .NET empowers developers to build smarter, more efficient applications that interact with Microsoft Graph.

Ready to build faster and more efficient .NET applications with Microsoft Graph?

See Also