Start Debugging

Tag: csharp

347 posts · Page 4 of 35

2026-09-17 comparison dotnet dotnet-11

Process.Run vs Process.Start in .NET 11: which should you use?

Use Process.Run when you start a tool and only care how it exited: one call, a timeout that kills the child, and a ProcessExitStatus with the signal. Keep Process.Start when you need the Process object: writing to stdin, reading output as it arrives, UseShellExecute, or killing a whole process tree.

2026-09-16 dotnet dotnet-11 jit

The .NET 11 JIT Devirtualizes Generic Virtual Methods, and the Allocation Goes With Them

Stephen Toub's Performance Improvements in .NET 11 post shows generic virtual method calls dropping from 6.7 ns and 24 bytes to 1.8 ns and zero allocation. Three RyuJIT pull requests unlocked inlining on the dispatch that used to be the most opaque one in .NET.

2026-09-16 errors dotnet dotnet-10

Fix: UIKitThreadAccessException from MediaPicker.PickPhotosAsync when selecting multiple photos in .NET MAUI iOS

Picking 2 or more photos on iOS throws UIKitThreadAccessException in MAUI 10.0.100 and 10.0.101. MAUI reads PHPickerResult.ItemProvider after an await, off the main thread. Pin 10.0.90, upgrade to 10.0.110, or use a PHPicker shim.

2026-09-15 errors aspnetcore dotnet-10

Fix: ASP.NET Core API endpoints return 401 instead of redirecting to the login page after upgrading to .NET 10

In .NET 10 cookie auth answers API-style endpoints with 401/403 instead of a login redirect. Restore it per endpoint, globally, or with an AppContext switch.

2026-09-15 errors ef-core ef-core-11

Fix: EF Core MigrateAsync and CanConnectAsync keep retrying on 'Login failed for user' for 60 seconds

EF Core's SQL Server existence check retries error 18456 for a full minute, with or without EnableRetryOnFailure. Fail fast, cap RetryTimeout, or wait for EF Core 12.

2026-09-15 dotnet ai microsoft-extensions-ai

Microsoft.Extensions.AI 10.10 Fails Evaluation Metrics the Judge Never Scored

Microsoft.Extensions.AI.Evaluation.Quality 10.10.0 now marks unparseable and out-of-range quality scores as failed, and Microsoft.Extensions.AI.OpenAI 10.10.0 drops the Assistants adapter. Measured before and after on 10.9.0.

2026-09-14 dapper dotnet csharp

Dapper 2.1.86 brings back DateOnly and TimeOnly, two years after pulling them

Dapper 2.1.86 re-enables built-in DateOnly and TimeOnly mapping for parameters, members, and scalars, with the column-offset and silent default(T) bugs fixed. What changed, what I measured, and what it means for your custom type handlers.

2026-09-14 dotnet-11 dotnet csharp

How to Create and Extract ZIP Files Asynchronously with the ZipArchive Async APIs in .NET 11

Use ZipFile.CreateFromDirectoryAsync, ExtractToDirectoryAsync, ZipArchive.CreateAsync and ZipArchiveEntry.OpenAsync without hidden synchronous I/O. Measured on .NET 11 RC 1 and .NET 10.0.12, including the .NET 10 bug that still blocks Kestrel.

2026-09-13 aspnetcore minimal-apis dotnet-11

How to bind a complex query-string object with [AsParameters] in a minimal API in ASP.NET Core 11

Put [AsParameters] on a class or record to bind a whole query-string filter in an ASP.NET Core 11 minimal API. Covers defaults, arrays, enums, nested objects, validation, OpenAPI, and a Native AOT generator bug with positional records.

2026-09-12 comparison csharp dotnet

Lookup<TKey, TElement> vs Dictionary<TKey, List<TValue>> for duplicate keys in C#

Use ToLookup when you group once and only read: it is immutable, returns an empty sequence for missing keys, accepts null keys and keeps first-seen order. Use Dictionary<TKey, List<TValue>> when the groups change after construction or cross a JSON boundary.