strtolower
Converts all alphabetic characters in a string to lowercase.
Parameters
main.php
Return Values
string
Returns the lowercased string
On success:String with all alphabetic characters converted to lowercase
On failure:Original string if no alphabetic characters found
Notes
- Function is binary-safe and locale-independent
- For multibyte strings, use mb_strtolower() instead
- Does not affect non-alphabetic characters
- Useful for case-insensitive comparisons and data normalization
Changelog
- Function has been available since PHP 4.0.0