AyCode.Core/AyCode.Utils/Extensions/README.md

Extensions

String, DateTime, and lock utility extensions.

Key Files

• StringExtensions.cs — IsNullOrEmpty(), IsNullOrWhiteSpace() (with [NotNullWhen]), FirstLetterToUpper(), MixCharacters() (interleaves two char sequences: ABC+DEF→ADBECF).
• DateTimeExtension.cs — IsNullOrEmpty() for DateTime/DateTime?, IsEqualSqlDateTime2() for SQL Server datetime2 precision comparison.
• LockExtensions.cs — using pattern for locks: mutex.UseWaitOne(), semaphore.UseWait(), semaphore.UseWaitAsync(). Returns IDisposable wrappers that auto-release on dispose.