(PHP 4, PHP 5)
strtolower — Make a string lowercase
Returns string with all alphabetic characters converted to lowercase.
Note that 'alphabetic' is determined by the current locale. This means that in i.e. the default "C" locale, characters such as umlaut-A (?) will not be converted.
The input string.
Returns the lowercased string.
Example #1 strtolower() example
<?php
$str = "Mary Had A Little Lamb and She LOVED It So";
$str = strtolower($str);
echo $str; // Prints mary had a little lamb and she loved it so
?>
Note: 本函数可安全用于二进制对象。