Half character? - Accents encoding issue - php

I'm currently facing a very strange encoding issue when dealing with an html source code.
I got the following line:
"requête présentée par..."
When an extern library does an utf8_decode I got:
"reque^te présente´e par..."
So accents are placed right to the accented characters. If I do an utf8_encode from that result, I don't get the original "requête présentée par..." but I keep having "reque^te présente´e par..."
Even stranger: If I open the original html in Notepad++, encoding is utf8 without BOM (so far, so good) but I can actually select half of the character with the text selection (keyboard or mouse). Yes, half of it. As if the real code was "e^" but it was displayed as "ê". When I try to copy it to my IDE it copies "ê" but pastes "e^".
I have come up with a basic replacement function:
"e^" => "ê",
"e´" => "é",
...
and some other french cases, and it's working properly for now.
But as the HTML comes in differents languages, I'm pretty sure I won't be able to successfully replace every character under this encoding issue.
Has anybody face this issue before and (hopefully) has a more general solution?
Thanks in advance.

It sounds like your HTML source is using Combining characters. That is, instead of using a single unicode character to represent the ê, it's using first a regular e and then a combining character to add the diacritic ^. You can verify this with a hex editor to see the character codes, in this case the combining circumflex is hex code 0302.
See also Unicode equivalence.

Related

UTF8 null character & normalizing whitespace characters

I'm working on a script that builds an XML feed using strings from the database. The strings are user-entered image captions from Facebook Open Graph API. The strings are supposed to be all UTF8 according to facebook. So i import the captions into the database and store them as utf8-unicode (i also tried utf8-bin)
But i always have the same error when trying to display the output XML feed, because one of the caption have a weird whitespace character
This page contains the following errors:
error on line 63466 at column 14: Input is not proper UTF-8, indicate encoding !
Bytes: 0x0B 0x54 0x68 0x6F
Below is a rendering of the page up to the first error.
In the database (phpmyadmin) and in the page source code (using chrome), the problematic characters appear as empty square symbol.
Now if i copy and paste the problematic character in an converter it gives me Hexadecimal 000B
What's the easiest way to fix this ?
I'd also like to understand in the first place, why Facebook Graph API is giving me non-utf8 characters when it's not supposed to
Failed attemps:
utf8_encode() isn't working because the rest of the strings are UTF8 valid.
I also tried multiple different ways of stripping out all non-utf8 characters, but it doesn't filter out this specific character. Same when trying to filter out all non-latin.
htmlentities() htmlspecialchars() or the same isn't encoding the problematic characters
charactericonv(mb_detect_encoding()) will not detect the string as invalid utf8
str_replace() or preg_replace() is of no help, if i try to copy and paste the character in Visual Studio Code, nothing is pasted, not even a whitespace
str_replace("\0", "", ) ...nope
Here is a list of what we have found and/or worked through with the original poster:
MySQL's utf-8 is not a proper implementation of utf-8 - utf8mb4 is;
additional information on character sets and collation differences;
changes that happen to existing data if collation is changed.
We have checked the above and discovered that the initial problem was caused by vertical tabulation symbols creeping into the text fields. A good way to remove said symbols is by running $str = str_replace("\x0b", "", $str);, where $str is the string that is going to be inserted into the text field. It's important to not replace \v, as that might not be desired.
If the 0B is always at the beginning of a string, then trace the strings back to their source and see if they are "BOM" encoded. Wikipedia on BOM .
At least come back with the various steps the data takes, so we can help with deducing the source of the problem.
Note: although needed for Emoji and Chinese, switching to utf8mb4 will not deal with BOM if that is the 'real' problem.
(using str_replace is just a bandaid)

Which middot character is this?

$string = 'Single · Female'
I copied it from facebook.
In html source its just that dot, how did they type it?
While echoing in php its A with circumflex (Â) concatenated with that same dot.
How can i explode this string with that dot?
It is U+00B7 MIDDLE DOT, a character used for many purposes, e.g. as a separator between links, alternatives, or other items.
If your code displays it as ·, then the reason is that the UTF-8 encoded form of U+00B7, namely 0xC2 0xB7, is being misinterpreted as being ISO-8859-1 or Windows-1252 encoded. You should fix this basic problem (instead of trying to deal with some of its symptoms). See UTF-8 all the way through.
Regarding the question “how did they type it?”, we cannot really know, and we need not know. There are zillions of ways to type characters, and anyone can invent a few more. (On my keyboard, I use AltGr Shift X. If I needed to type “·” on a Windows computer with vanilla settings, I would use Alt 0183.)
I believe this is an interpunct. It can be used through the HTML entities · or · and in PHP with the unicode value U+00B7.
If you want to echo the unicode character without HTML entities, you can set the character encoding to UTF-8. Splitting is done through explode("·", $textToSplit) given that your PHP file is using UTF-8 as character encoding.

Bullet "•" in XML

Similar to this question
I am consuming an XML product that has some illegal chars in it. I seriously doubt I can get them to fix the problem, but I will try. In the meantime I'd like a work-around.
The problem is that it contains a bullet. It renders as "•" in my source. I've tried a few encoding conversions but have not found a combination that works. (I'm not accustomed to even thinking about my encoding type, so I'm out of my element here.) So, I tried the below and it seems that str_replace does not recognize the "•". (it renders as tall block in my text editor)
You can see the commented lines where I tried a few different things.
I tried str replace on "•" first, then tweaked around and this is my latest:
// deal with bullets in XML.
$bullet="•"; //this was copied and pasted from transliterated text.
//$data=iconv( "UTF-8", "windows-1252//TRANSLIT", $data ); //transliterate the text:
//$data=str_replace($bullet,'•',$data); // replace the bullet char
$data=str_replace($bullet,' - ',$data); // replace the bullet char
//$data=iconv( "windows-1252", "UTF-8", $data ); // return the text to utf-8 encoding.
Any ideas how to strip or replace this char? If there's a function to pre-clean the XML, that'd be great, and I wouldn't have to worry about it.
XML by definition has no illegal chars. If some string contains a character that is not part of XML, then that string is not XML by definition.
The character you're concerned about is part of Unicode. As XML is based on Unicode, this is good news. So let's name what you aim for:
Unicode Character 'BULLET' (U+2022)
So you now say it renders as •. Because U+2022 is encoded as 0xE2 0x80 0xA2 in UTF-8, it is a more or less safe assumption to say that you take an UTF-8 encoded string (that is the default encoding used in XML btw) but command the software that renders it to treat it as some single-byte encoding hence turning the single code-point into three different characters:
Unicode Character 'LATIN SMALL LETTER A WITH CIRCUMFLEX' (U+00E2)
Unicode Character 'EURO SIGN' (U+20AC)
Unicode Character 'CENT SIGN' (U+00A2)
Instead you need to command the rendering application to use the UTF-8 encoding. That should immediately solve your issue. So find the place where you introduce the wrong encoding, you will likely not need to re-encode it, just to properly hint the encoding.
If you wonder which single-byte character-encodings have these three Unicode Characters at the corresponding bytes (0xE2 0x80 0xA2), here is a list. I have highlighted the most popular one of these:
ISO-8859-15 (Latin 9)
OEM 858 (Multilingual Latin I + Euro)
Windows 1252 (Latin I)
Windows 1254 (Turkish)
Windows 1256 (Arabic)
Windows 1258 (Vietnam)

Strange behaviour when encoding cURL response as UTF-8

I'm making a cURL request to a third party website which returns a text file on which I need to do a few string replacements to replace certain characters by their html entity equivalents e.g I need to replace í by í.
Using string_replace/preg_replace_callback on the response directly didn't result in matches (whether searching for í directly or using its hex code \x00\xED), so I used utf8_encode() before carrying out the replacement. But utf8_encode replaces all the í characters by Ã.
Why is this happening, and what's the correct approach to carrying out UTF-8 replacements on an arbitrary piece of text using php?
*edit - some further research reveals
utf8_decode("í") == í;
utf8_encode("í") == í;
utf8_encode("\xc3\xad") == í;
utf8_encode is definitely not the way to go here (you're double-encoding if you do that).
Re. searching for the character directly or using its hex code, did you make sure to add the u modifier at the end of the regex? e.g. /\x00\xED/u?
You're probably specify the characters/strings you want replaced via string literals in the php source code? If you do, then the values of those string literals depends on the encoding you save your php file in. So while you see the character í, maybe the literal value is a latin encoded í, like maybe 8859-1 encoding, or maybe its windows cp1252 í, or maybe its utf8 í, or maybe even utf32 í...i dont know off hand how many of those are different, but i know at least some have different byte representations, and so wont match in a php string comparison.
my point is, you need to specify the correct character that will match whatever encoding your incoming text is in.
heres an example without using literals
$iso8859_1 = chr(236);
$utf8 = utf8_encode(chr(236));
be warned, text editors may or may not convert the existing characters when you change the encoding, if you decide to change the file encoding to utf8. I've seen editors do really bizarre things when changing the encoding. Start with a fresh file.
also-just because the other server claims its utf8, doesn't mean it really is.

PHP: html_entity_decode removing/not showing character

I am having a problem with  character on my website.
I have a website where users can use a wysiwyg editor (ckeditor) to fill out their profile. The content is ran through htmlpurify before being put into a database (for security reasons).
The database has all tables setup with UTF-8 charset. I also call 'SET NAMES utf-8' at the beginning of script execution to prevent problems (which has worked for years, as I haven't had this problem in a long time). The webpage the text is displayed on has a content-type of utf-8 and I also use the header() function to set the content-type and charset as well.
When displaying the text all seemed fine until I tried running a regular expression on the content. html_entity_decode (called with the encoding param of 'utf-8') is removing/not showing the  character for some reason and it leaves behind something which is causing all of my regexes to fail (it seems there is a character there but I cannot view it in the source).
How can I prevent and/or remove this character so I can run the regular expression?
EDIT: I have decided to abandon ckeditor and go with the markdown format like this site uses to have more flexibility. I have hated wysiwyg editors for as long as I remember. Updating all the profiles to the new format will give me a chance to remove all of the offending text and give the site a clean start. Thanks for all the input.
You are probably facing the situation that the string actually is not properly UTF-8 encoded (as you wrote it is, but it ain't). html_entity_decode might then remove any invalid UTF-8 byte sequences (e.g. single-byte-charset encoding of Â) with a substitution character.
Depending on the PHP version you're using you've got more control how to deal with this by making use of the flags.
Additionally to find the character you can't see, create a hexdump of the string.
Since the character you are talking about exists within the ANSI charset, you can do this:
utf8_encode( preg_replace($match, $replace, utf8_decode($utf8_text));
This will however destroy any unicode character not existing within the ANSI charset. To avoid this you can always try using mb_ereg_replace which has multibyte (unicode) support:
string mb_ereg_replace ( string $pattern , string $replacement , string $string [, string $option = "msr" ] )

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