IntlChar::tolower

(PHP 7)

IntlChar::tolower — Make Unicode character lowercase

Descrierea

public static IntlChar::tolower ( mixed $codepoint ) : mixed

The given character is mapped to its lowercase equivalent. If the character has no lowercase equivalent, the original character itself is returned.

Parametri

codepoint: Valoarea codepoint de tip integer (de ex. 0x2603 pentru U+2603 SNOWMAN) sau caracterul codificat ca string în UTF-8 (de ex. "\u{2603}")

Valorile întoarse

Returns the Simple_Lowercase_Mapping of the code point, if any; otherwise the code point itself.

Tipul întors va fi integer, doar dacă code point nu a fost transmis ca string UTF-8, în care caz va fi întors un string.

Exemple

Example #1 Testarea diferitor 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")));
?>

Exemplul de mai sus va afișa:

string(1) "a"
string(1) "a"
string(2) "φ"
string(2) "φ"
string(1) "1"
int(97)
int(97)

A se vedea și

IntlChar::totitle() - Make Unicode character titlecase
IntlChar::toupper() - Make Unicode character uppercase
mb_strtolower() - Make a string lowercase

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User Contributed Notes 1 note

down

Patanjali ¶

4 years ago


The other function I wrote to replace mb_strtolower may not work properly, as it erroneously equated graphemes with codepoints.

tolower, like many IntlChar methods, works specifically on codepoints, so requires a codepoint iterator to isolate each.

Also, because in tolower, if there is no lowercase version of the codepoint, the supplied one is returned, so there is no need to specially test for alphabetic codepoints before conversion.

<?php 
function u_tolower($text=''){
// if blank, return blank (don't waste CPU cycles)
if($text==''){return'';}

// create the codepoint break iterator to identify the start of each codepoint
$iterator=IntlBreakIterator::createCodePointInstance();

// load the text
$iterator->setText($text);

// using a parts iterator to extract each codepoint itself, convert and append it to the new string
$newtext='';
foreach($iterator->getPartsIterator() as $codepoint){$newtext.=IntlChar::tolower($codepoint);}

// return converted text
return $newtext;
}
?>

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