http://www.nicknettleton.com/zine/php/php-utf-8-cheatsheet
http://www.phpwact.org/php/i18n/charsets%23checking_utf-8_for_well_formedness
also:
A. GOOD LINKS TO UNDERSTANDING UNICODE
1. a short/friendly intro to unicode- minimal needed for programmers:
http://www.joelonsoftware.com/articles/Unicode.html
2. a good explanation of how windows-1252 character set differs from
normal us-ascii (aka 'iso-8859-1', aka 'latin-1'), and the problems
this creates:
http://en.wikipedia.org/wiki/Windows-1252
3. a quick cheat-sheet (only for someone who would be technically
interested) on how to programmatically character-by-character
convert us-ascii to utf-8. we don't need to know this as php
programmers. just fyi only:
http://intertwingly.net/stories/2004/04/14/i18n.html#utf8
B. CONVERTING FROM ONE CHARSET TO ANOTHER IN PHP
1. there are several ways to do it. one is with the iconv() php call:
$utf8_string = iconv("windows-1252", 'utf-8', $windows1252_string);
2. however, conversions like the above should most often be
unecessary, if all incoming and outgoing web-pages are in
utf-8. this means even html pages containing forms: if the page
containing the form is in utf-8, then even with people cutting and
pasting text in from windows-1252 on their windows machines, the
browser program they use will automatically convert and submit the
form's text into utf-8.
C. RECOMMENDED POLICY: thus, all our web pages should be in utf-8. and
the data stored in the database should be in utf-8. even XML defaults
to utf-8. so everything coming and going will be in the same
universally-recognized character set.
D. CONFIGURING WEB SERVER
1) apache's default character set:
if your web server's httpd.conf file still has a line reading:
AddDefaultCharset ISO-8859-1
then change it to:
AddDefaultCharset UTF-8
and restart:
/sbin/service httpd restart
NOTE: I've already done this for web1 and our two xml servers (apache
on fedora core 4 comes with UTF-8 as default character set, anyway).
2) tags in section:
the tag embedded in an .html file itself is not so important.
as far as i can tell, both ie and firefox ignore it. perhaps they only
pay attention to it if the charset is missing from the http header??
in any case, to be careful, you should either delete it completely, or
re-do it from:
to
3) header() php commands
if you have any
header("Content-type: text/html; charset=iso-8859-1");
commands in your .php scripts, then change them to:
header("Content-type: text/html; charset=utf-8");
or just delete them completely (since the web server now defaults to
utf-8 because of changes made in step 1.).