BestPractice - Transform first character of a string into lower case

Question

I\'d like to have a method that transforms the first character of a string into lower case.

My approaches:

1.

public static string ReplaceFir         


        

Answer 1

Combined a few and made it a chainable extension. Added short-circuit on whitespace and non-letter.

public static string FirstLower(this string input) => 
    (!string.IsNullOrWhiteSpace(input) && input.Length > 0 
        && char.IsLetter(input[0]) && !char.IsLower(input[0]))
    ? input[0].ToString().ToLowerInvariant() + input.Remove(0, 1) : input;