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C# “Regex Is Slow as Hell” — Missing Compiled Option

- 12.12.25 - ErcanOPAK

If regex is used repeatedly:

var r = new Regex(pattern);

→ insanely slow.

✔ Right Way

var r = new Regex(pattern, RegexOptions.Compiled);

💡 Speed Boost

Up to 20× faster on repeated matches.

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Clean Dependency Injection — Lifetimes That Every Dev Must Master

The Null Coalescing Assignment Operator (??=)

Static State Causes Test Flakiness

Post Views: 4

Post navigation

C# “LINQ Select N+1 Disaster” — Why Your Code Makes 500 SQL Calls
SQL “Scalar Functions Destroy Performance” — The Hidden Anti-Pattern

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