Start Debugging

Tag: csharp

246 posts · Page 1 of 25

2026-07-23 comparison csharp dotnet

Typed results (Results<>) vs IResult vs IActionResult in ASP.NET Core 11

In ASP.NET Core 11, return Results<T1, TN> with TypedResults for minimal APIs and ActionResult<T> for controllers. Treat bare IResult and bare IActionResult as escape hatches: they compile for any response but describe nothing to OpenAPI, so you pay for them in hand-written ProducesResponseType attributes.

2026-07-23 comparison aspnetcore dotnet-11

WebApplication.CreateBuilder vs CreateSlimBuilder vs CreateEmptyBuilder in ASP.NET Core 11

Use CreateBuilder for a normal app, CreateSlimBuilder when you publish trimmed or Native AOT behind a TLS proxy, and CreateEmptyBuilder only when you want to register every service yourself. Here is the feature matrix and the gotchas that force the call.

2026-07-22 comparison aspnetcore dotnet-11

Output caching vs response caching in ASP.NET Core 11: which should you use?

Output caching is the right default for almost every server-side app in ASP.NET Core 11. Response caching only wins when your goal is to steer browser and proxy caches through HTTP headers. Here is the decision, with a feature matrix and the gotchas that force the call.

2026-07-21 comparison microsoft-agent-framework ai-agents

Microsoft Agent Framework orchestration: sequential vs concurrent vs group chat vs handoff vs magentic

Sequential for pipelines, concurrent for fan-out, group chat for moderated rounds, handoff for routing, magentic for open-ended planning. The C# builders and how to choose.

2026-07-21 errors csharp csharp-14

Fix: CS4014 "Because this call is not awaited, execution of the current method continues" in C#

CS4014 means you called a Task-returning method without awaiting it. Add await, or discard with _ = if fire-and-forget is truly intended, and handle exceptions.

2026-07-21 errors csharp dotnet

Fix: System.InvalidOperationException: Sequence contains no elements

This exception means you called .First() or .Single() on an empty sequence. Use FirstOrDefault/SingleOrDefault and null-check, or guard the query, or fix why the source is empty.

2026-07-21 csharp dotnet-11 system-text-json

System.Text.Json Learns to Serialize C# Union Types in .NET 11 Preview 6

How System.Text.Json in .NET 11 Preview 6 serializes the new C# union types by writing the active case, and the JsonUnionAttribute and type-classifier APIs that handle ambiguous cases.

2026-07-20 aspnetcore dotnet-11 validation

Async validation lands in Minimal APIs with .NET 11 Preview 6

Preview 6 adds AsyncValidationAttribute and IAsyncValidatableObject so DataAnnotations rules can hit the database before your endpoint runs, without blocking a thread.

2026-07-20 errors csharp csharp-14

Fix: CS8618 "Non-nullable property must contain a non-null value when exiting constructor" in C#

CS8618 means a non-nullable field or property was not initialized by the time the constructor finished. Set it in the constructor, give it a default, mark it required, or make it nullable.

2026-07-20 csharp dotnet dotnet-11

Fix: deadlock when calling .Result or .Wait() on an async method in C#

Blocking on an async Task with .Result or .Wait() deadlocks when a SynchronizationContext is present. Here is why it hangs and how to fix it in .NET 11 and C# 14.