Do not use ToLower() method for string comparison

Don’t use .ToLower() for string comparison. Why not?

1. Performance Issues:
   The .ToLower() method creates a new string in memory every time it’s called, leading to unnecessary memory allocations, especially in high-frequency operations.

2. Culture Sensitivity:
   The .ToLower() method is culture-sensitive, which means results may vary depending on the current culture set for the executing thread.

What’s the Better Alternative?

Use the .NET enumeration StringComparison for more efficient and reliable string comparisons. ✅

StringComparison Options:

• Ordinal:
  Use for general-purpose comparisons where culture doesn’t matter. This is the fastest option.

• OrdinalIgnoreCase:
  Use for case-insensitive comparisons without cultural rules.

• CurrentCulture & CurrentCultureIgnoreCase:
  Best for comparing user-facing strings, as they adhere to the current culture’s rules.

• InvariantCulture & InvariantCultureIgnoreCase:
  Ideal for consistent results across different cultures, often used in data storage and retrieval scenarios.

Important Note:
If you’re using Entity Framework Core, methods like String.Equals(String, StringComparison) cannot be translated into SQL and will throw an exception. Be cautious when applying StringComparison in LINQ queries.

Source 🔗 https://thecodeman.net/