Server-Sent Events (SSE) in .NET 10 provide a lightweight alternative to SignalR for one-way real-time communication from server to client. The new TypedResults.ServerSentEvents API enables streaming data over HTTP with built-in reconnection support and Last-Event-ID handling. SSE works over plain HTTP, requires minimal setup, and is ideal for live feeds, notifications, and progress tracking where bidirectional communication isn't needed. The implementation includes creating async enumerable streams, handling reconnections, and consuming events via JavaScript's EventSource API.
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What Are Server-Sent EventsCommon Use Cases:Implementing SSE in ASP.NET Core 10Reconnection Logic and the Last-Event-ID HeaderTesting SSE Endpoint with an HTTP FileHow to Subscribe to Server-Sent Events from the FrontendSSE vs. SignalR (WebSockets)SummarySort: