PHP: Convert html-entity-encoded uppercase character to lowercase

Question

How can I convert the upper-case html entity characters to their lowercase?

$str = "&#xC9;"; //É

$res = strtolower( $str );

echo $res;

score 8 · Answer 1 · answered Dec 30 '12 at 14:24

8

Just use the right function for it:

$strLower = mb_strtolower($str, 'HTML-ENTITIES');

answered Dec 30 '12 at 14:24

hakre

score 7 · Accepted Answer · answered Dec 30 '12 at 14:09

7

$str = "&#xC9;"; //É

$res = mb_strtolower(html_entity_decode($str,ENT_COMPAT|ENT_HTML401,'UTF-8'),'UTF-8' );

echo $res;

answered Dec 30 '12 at 14:09

dev-null-dweller

`Warning: html_entity_decode() expects parameter 2 to be long, string given in /in/F6TSA on line 4` http://3v4l.org/F6TSA – John Dvorak Dec 30 '12 at 14:13
Works in PHP 5.4+ now, generates a notice in 5.0-5.3 (`Use of undefined constant ENT_HTML401`): http://3v4l.org/uWbbu – John Dvorak Dec 30 '12 at 14:15
well, I misplaced encoding argument at first – dev-null-dweller Dec 30 '12 at 14:16
@AlixAxel It does work for `É`. Any example of an uppercase that doesn't convert properly? – John Dvorak Dec 30 '12 at 14:19
@JanDvorak: `É` is Latin-1. Try any Greek letter for instance. – Alix Axel Dec 30 '12 at 14:25
@JanDvorak: You're still using the Latin alphabet. Try `ΕΛΛΗΝΙΚΉ ΓΛΏΣΣΑ`. – Alix Axel Dec 30 '12 at 14:29
@AlixAxel What you have posted is already lowercase but it converts to uppercase correctly: http://3v4l.org/Rv3cI – John Dvorak Dec 30 '12 at 14:29
@AlixAxel any other challenge? – John Dvorak Dec 30 '12 at 14:32
@JanDvorak: The point was converting hexits to lowercase, hence `$str = ΕΛΛΗΝΙΚΉ ΓΛΏΣΣΑ`. Either way, I just tested it and it works with `html_entity_decode`, which is a bit weird because I remember testing it against `mb_convert_encoding` and the charset support was not so extensive back then. – Alix Axel Dec 30 '12 at 14:47

Alix Axel · Answer 3 · 2012-12-30T14:21:41.650

1

Convert the hexit to decimal and add 32, convert back to hexit.

Or using mbstring:

$res = mb_strtolower(mb_convert_encoding($str, 'UTF-8', 'HTML-ENTITIES'), 'UTF-8')

edited Dec 30 '12 at 14:21

answered Dec 30 '12 at 14:10

Alix Axel

It's add 32 to get from uppercase to lowercase. – irrelephant Dec 30 '12 at 14:11
@JanDvorak: No, it works for Latin-1 too (with the exception of [`yY`] + `¨`). – Alix Axel Dec 30 '12 at 14:13
1

@AlixAxel A solution is searched for that works in the entire unicode range. – John Dvorak Dec 30 '12 at 14:14
@JanDvorak: Humm... Okay. I'll post something else then. – Alix Axel Dec 30 '12 at 14:17
Nice one, but rather useless with named entites like `Ü` – dev-null-dweller Dec 30 '12 at 14:21
I was commenting before edit. Useless when you don't have hex value in entity. – dev-null-dweller Dec 30 '12 at 14:28

score 0 · Answer 4 · answered Mar 10 '14 at 09:52

0

On my server, I don't have the mbstring extension installed. For a better, cross-server solution you should use this instead:

echo htmlentities(strtoupper(html_entity_decode($str)));

answered Mar 10 '14 at 09:52

Julian F. Weinert

4 Answers4