.NET Framework环境下是否应使用Microsoft.Azure.EventHubs.Processor库？

Great question—this confusion is totally understandable given the mixed signals from outdated examples and official announcements. Let me break this down for you clearly:

Yes, you should move away from Microsoft.Azure.ServiceBus.EventProcessorHost #

The 2017 Microsoft announcement you found is still aligned with their long-term strategy:

• The Microsoft.Azure.EventHubs.Processor library uses a unified codebase that works across both .NET Framework and .NET Core/.NET 5+, meaning all future updates, bug fixes, and new Event Hubs features will be delivered here.
• The older EventProcessorHost lives in the separate Microsoft.Azure.ServiceBus library, which has diverged from Event Hubs-specific tooling. Microsoft has been guiding users to Event Hubs-native processor libraries for years, and legacy support for the Service Bus-based processor will eventually wind down.

Why do official examples still recommend the old library? #

This is almost certainly due to documentation and sample lag. Microsoft’s example repos and docs often take time to catch up with strategic shifts, especially when supporting legacy runtimes like .NET Framework. Those examples are likely retained for users stuck on very old .NET Framework versions (pre-4.6.1), but if your project runs .NET Framework 4.6.1 or later, the newer processor libraries are fully compatible.

Bonus: Skip straight to the latest library if possible #

Note that Microsoft has since released Azure.Messaging.EventHubs.Processor (part of the Azure SDK v2 family), which is the current, most actively maintained choice for all .NET runtimes (including .NET Framework 4.6.1+). If you’re planning a migration, you might want to jump directly to this version instead of Microsoft.Azure.EventHubs.Processor, as it has a more modern async-first API, better performance, and will receive the longest-term support.

Key benefits of switching #

• Unified maintenance: You’ll get access to the latest Event Hubs features (like improved checkpointing, batch processing) and critical bug fixes without waiting for separate updates to the Service Bus library.
• Future-proofing: Avoid being stuck with an unmaintained library as Microsoft phases out support for legacy Event Hubs tooling.
• Consistent API: The newer processors align with modern .NET best practices, making your code easier to maintain and adapt if you ever move to .NET Core/.NET 8 in the future.

Things to consider before migrating #

• Migration effort: You’ll need to update your NuGet packages, replace namespaces (e.g., from Microsoft.Azure.ServiceBus to Azure.Messaging.EventHubs.Processor), and adjust your event processing logic (e.g., switching from IEventProcessor to using ProcessEventAsync and ProcessErrorAsync handlers with EventProcessorClient).
• Niche feature checks: If your code relies on specific rare features of the old EventProcessorHost, test those scenarios thoroughly with the new library to ensure parity. For standard data ingestion use cases, the feature set is fully compatible.

Content of the question comes from Stack Exchange, asked by Francis MC