(PHP 7)
IntlChar::tolower — Make Unicode character lowercase
The given character is mapped to its lowercase equivalent. If the character has no lowercase equivalent, the original character itself is returned.
Returns the Simple_Lowercase_Mapping of the code point, if any; otherwise the code point itself.
The return type will be integer unless the code point was passed as a UTF-8 string, in which case a string will be returned.
Example #1 Testing different code points
<?php
var_dump(IntlChar::tolower("A"));
var_dump(IntlChar::tolower("a"));
var_dump(IntlChar::tolower("Φ"));
var_dump(IntlChar::tolower("φ"));
var_dump(IntlChar::tolower("1"));
var_dump(IntlChar::tolower(ord("A")));
var_dump(IntlChar::tolower(ord("a")));
?>
以上例程会输出：
string(1) "a" string(1) "a" string(2) "φ" string(2) "φ" string(1) "1" int(97) int(97)