Let's suppose that an chracter encoding format called X exists (for example UTF-8), if I insert in the HTML file the tag <meta charset="X"> and then I save the file, obviously, with the same encoding, how can the broswer read the file later?
I mean, how can the broswer know the encoding of an HTML page if, to get encoding, it must read the file? It seems a sort of loop.
According to https://www.w3.org/TR/html4/charset.html#h-5.2.2, a browser gets the correct encoding from the Content-Type header field of the HTTP response. If this field is not present, the browser reads the HTML page until the META tag, assuming all bytes were ASCII characters. So this only works if ASCII is a subset of the actual encoding.
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In Dreamweaver I have the option "Include Unicode Signature (BOM)".
If I check this box and save the file the HTML file it looks good when viewed in the web browser. If not it gives me strange symbols for Swedish letters like åäö.
If I serve this HTML file with strange letters using the header respond "Content-Type: text/html; charset=utf-8" it still gives me strange symbols.
Q1) Does that mean that it's not a UTF-8 encoded file (the one without BOM that shows strange symbols)?
Q2) What makes a file UTF-8 encoded, is it just the Unicode signature (BOM)?
Q3) Should I or should I not add the Include Unicode Signature (BOM) in my files (HTML, Javascript, CSS, PHP)?
I know that I can add <meta charset="UTF-8"> in the HTML code or type AddDefaultCharset UTF-8 in my .htaccess. I just figure the optimal solution would be to have a header respond that says "it's a UTF-8 encoded file" and then also actually serve a UTF-8 encoded file. Nothing else.
Q4) I thought HTML files were plain text-files. What other information is hidden in those files and how can I read this information?
The BOM is entirely optional for UTF-8. The Unicode consortium points out that it can create problems while offering no real advantage; the W3C says that it can be a substitute for other forms of declaring the encodings and should work on all modern browsers.
The BOM is only there to clarify the endianness of the encoding. Since UTF-8 only has one kind of endianness it is superfluous. It's only useful for UTF-16 and other encodings. A UTF-8 encoded file is UTF-8 encoded regardless of the presence of the BOM.
HTML files do not "hide" any other information, they're plain text.
My recommendation would be:
encode as UTF-8 without BOM
add the HTTP Content-Type header to denote the encoding of the file
also add the <meta> tag into the HTML itself as a fallback, should the file be interpreted outside of an HTTP context (meaning where no HTTP header exists because the file is not read over HTTP)
This gives you the best compatibility with the least potential for issues. If your characters are still appearing funny, then your file is not actually UTF-8 encoded or the HTTP header is not being set correctly.
When I design a html page in Dreamweaver CS6 I use its validation tool (it sends the code to w3c) and I get no errors. However, when I validate the same page in UltraEdit 21 (it uses HTML Tidy) I get the warning:
"Specified input encoding (utf-8) does not match actual input encoding (utf-16)"
The page is set as html5 (with <!doctype html>), as utf-8 (with <meta charset="utf-8">) and contains greek text.
Well, the question is:
Does that problem affect the appearance of the page? I mean, when I publish it, will a user in China, Germany, or ...Tierra del Fuego see the greek text?
If yes, the rest are less important, but I'll ask them:
What makes HTML Tidy to define the document as utf-16? Is there a character, word or visible string of any kind that I can remove/delete to correct the problem?
If I use <meta charset="utf-16"> will browsers parse the code correctly (ending to greek text for the global user)?
The actual file encoding will be set in Dreamweaver properties for the file.
Dreamweaver Help / Set title and encoding properties for a page:
The Title/Encoding Page Properties options let you specify the document encoding type that is specific to the language used to author your web pages as well as specify which Unicode Normalization Form to use with that encoding type.
Select Modify > Page Properties, or click the Page Properties button in the text Property inspector.
Choose the Title/Encoding category and set the options.
...
Encoding
Specifies the encoding used for characters in the document.
If you select Unicode (UTF‑8) as the document encoding, entity encoding is not necessary because UTF‑8 can safely represent all characters. If you select another document encoding, entity encoding may be necessary to represent certain characters. For more information on character entities, see www.w3.org/TR/REC-html40/sgml/entities.html.
...
Include Unicode Signature (BOM)
Includes a Byte Order Mark (BOM) in the document. A BOM is 2 to 4 bytes at the beginning of a text file that identifies a file as Unicode, and if so, the byte order of the following bytes. Because UTF‑8 has no byte order, adding a UTF‑8 BOM is optional. For UTF‑16 and UTF‑32, it is required.
Choose UTF-8 without BOM.
UltraEdit automatically detects encoding of a file on opening and displays it at bottom in status bar. See in UltraEdit Advanced - Configuration - File Handling - Unicode/UTF-8 Detection and press button Help for some more details.
UTF-16 is displayed for a file encoded in UTF-16 Little Endian with or without BOM on using standard status bar since UE v19.00. Clicking on this list box in status bar and selecting Unicode - UTF-8 results in converting the file from UTF-16 LE to UTF-8 which then matches with the character set declaration in head of your HTML5 file.
When using basic status bar in UE v19.00 or any later version or using any UltraEdit version prior v19.00, the status bar field right to the field with line, column and clipboard number starts with U- for a file with UTF-16 LE encoding.
The UltraEdit help page about the Status Bar contains more information about information shown in standard and basic status bar in UltraEdit.
Conversion to UTF-8 can be done with UltraEdit also with command UNICODE/UTF-8 to UTF-8 (Unicode Editing) in submenu Conversions in menu File.
There are 2 configuration settings at Advanced - Configuration - File Handling - Save which define saving a UTF-8 encoded file with or without byte order mark (BOM):
Write UTF-8 BOM header to all UTF-8 files when saved
Write UTF-8 BOM on new files created within this program (if above is not set)
As UTF-8 encoded HTML files should be always without BOM, it is better to have both UTF-8 BOM settings unchecked when using UltraEdit mainly for editing HTML files.
Another possibility to convert a file with UltraEdit is using command Save As from menu File and use appropriate Encoding / Format setting. UTF-8 in Save As dialog means saving the file as UTF-8 encoded file with BOM and UTF-8 - NO BOM without BOM independent on the two configuration settings for standard Save.
For converting all files in a single folder, a folder tree, opened in UltraEdit, etc. to UTF-8 using UltraEdit, there is an UltraEdit scripting solution, see How to convert all files in a folder to UTF-8?
Unfortunately UE v21.30.0.1024 still does not recognize the short character set declaration <meta charset="utf-8"> as defined in HTML5 standard. See Short utf-8 charset declaration in HTML5 header with details about this limitation and how it can be worked around. This limitation does not matter if within first 64 KB at least one UTF-8 encoded character is found as it will be the case for your HTML5 files with Greek text.
HTML Tidy installed with UltraEdit v21.30.0.1024 is of version 25 March 2009. I'm not sure if HTML Tidy really supports short charset declaration of HTML5. But it looks so because otherwise you would not see the warning on validating the HTML5 file with HTML Tidy.
It might be useful for you to read UltraEdit power tip Unicode text and Unicode files in UltraEdit/UEStudio as it looks like you do not really know what encoding and character set really means and why it is important for applications that the declaration in the HTML5 matches with really used encoding.
I answer your questions now after all those general UltraEdit stuff.
Does that problem affect the appearance of the page?
Although the file contains the declaration that file contents is encoded with UTF-8, but is in real encoded with UTF-16 Little Endian, the browsers display the contents correct. UTF-16 detection is very easy, especially with BOM present and therefore browsers ignore wrong declaration and interpret the bytes of the HTML file from beginning right as UTF-16 encoded text file.
However, it would be much better to convert the UTF-16 encoded HTML files to UTF-8 without BOM. UTF-8 without BOM is most commonly used for HTML files worldwide and then the character set declaration in head of your HTML file would also match with really used encoding.
What makes HTML Tidy to define the document as utf-16?
The really used encoding of your HTML file is UTF-16 Little Endian and UltraEdit, HTML Tidy and the browsers detect that already after reading in the first 2 bytes of the text file - the byte order mark. That's the reason why HTML Tidy suggests to declare the encoding in head of HTML file correct as utf-16 as the file is really encoded with.
If I use <meta charset="utf-16"> will browsers parse the code correctly?
In case of keeping the file encoded in UTF-16 LE (always 2 bytes per character), it would be better to declare the character set right with <meta charset="utf-16">. But no Unicode aware text editor or browser has a problem to automatically detect UTF-16 Little Endian encoding with byte order mark.
The character set declaration becomes very important mainly for UTF-8 encoded files (1, 2, 3 or even 4 bytes per character) or files with single-byte coded characters using a code page like Windows-1252 / ISO 8859-1 (Latin 1) or Windows-1253 / ISO 8859-7 (Latin/Greek).
You can send the charset both in the http response headers and also you can define a charset in the html file you have sent..
What happens if these 2 are different charsets? How does the browser use the charset for what it received in the http headers and where does it matter what charset it provided in the html file itself?
The HTML 4.01 specification clearly says, in 5.2.2 Specifying the character encoding, that information in an HTTP header has precedence over a meta tag. HTML5 PR does not change this, but it adds, reflecting browser practice, in 8.2.2.2 Determining the character encoding that both of them are overridden by a Byte Order Mark (BOM) at the start of the HTML document (so if you have saved your .html file with “Save as UTF-8 with BOM”, it will be treated as UTF-8 no matter what).
A meta tag that specifies character encoding takes effect if the information is not provided in an HTTP header or with a BOM. A server might not include charset parameter in the Content-Type header, or the HTML document might be opened locally so that there are no HTTP headers at all. When a user saves an HTML document in his own device, the HTTP headers are not saved. This is the main reason for using a meta tag to specify character encoding; but it should then specify the correct encoding of course.
It is as the title says:
HTML - When using UTF-8 or ISO-8859-1 do I still need to type the codes for the special characters?
Or can I just type them normally?
Ex: I'm using UTF-8 in my HTML META tag. I need to type ç should I just type it or type its code which is ç
I know this is a trivial question, but it's fundamental so I just can't skip it.
No, you only need to use a character reference if:
The character you want cannot be represented in the character encoding you are using or
The character has some special meaning in HTML (such as < or &).
Note that declaring you are using UTF-8 in the meta tag is insufficient. You also have to encode the HTML source in UTF-8 (good editors will default to this) and not override it with a declaration of some other encoding in the real HTTP headers. You should also set the real HTTP headers to state that UTF-8 is being used.
Yes, you can include those characters directly in your HTML source, without using the entity for the character. Just make sure that the encoding you are saving the file in really does match what the web server serves it in.
The part about ensuring that the encoding is correct is important, and easy to get wrong. One thing to note is that the meta tag is not the primary source of information that the browser uses for interpreting the encoding of the document. The primary source of information is the Content-type header, sent as part of the HTTP headers. The meta tag was originally supposed to be used to communicate to the web server what Content-type to use, but most web servers use configuration separate from the document itself for this. So if you are saving your document as UTF-8, make sure that the web server is configured to serve pages as UTF-8 as well.
The meta tag is used by browsers as a fallback if the Content-type header is not provided or does not include valid encoding information. It is useful to have if you are ever going to be loading from a source that doesn't provide Content-type information, like using a file: URL to view the page on your local machine.
So, there are 3 places you should make sure your encoding is set up properly; in your text editor (so that it saves the file with the appropriate encoding), in your web server configuration (so that it communicates the appropriate encoding to the browser), and in the meta tag, so that when you view the page locally, it is displayed with the correct encoding.
Finally, you shouldn't use ISO-8859-1. That's a legacy encoding, only still supported for compatibility. Every major browser and text editor supports UTF-8 by now, which covers all of Unicode, and provides a lot fewer encoding headaches.
I want to simply display the tick (✔) and cross (✘) symbols in a HTML page but it shows up as either a box or goop ✔ - obviously something to do with the encoding.
I have set the meta tag to show utf-8 but obviously I'm missing something.
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
Edit/Solution: From comments made, using FireBug I found the headers being passed by my page were in fact "Content-Type: text/html" and not UTF-8. Looking at the file format using Notepad++ showed my file was formatted as "UTF-8 without BOM". Changing this to just UTF-8 the symbols now show correctly... but firebug still seems to indicate the same content-type.
You should ensure the HTTP server headers are correct.
In particular, the header:
Content-Type: text/html; charset=utf-8
should be present.
The meta tag is ignored by browsers if the HTTP header is present.
Also ensure that your file is actually encoded as UTF-8 before serving it, check/try the following:
Ensure your editor save it as UTF-8.
Ensure your FTP or any file transfer program does not mess with the file.
Try with HTML encoded entities, like &#uuu;.
To be really sure, hexdump the file and look as the character, for the ✔, it should be E2 9C 94 .
Note: If you use an unicode character for which your system can't find a glyph (no font with that character), your browser should display a question mark or some block like symbol. But if you see multiple roman characters like you do, this denotes an encoding problem.
I know an answer has already been accepted, but wanted to point a few things out.
Setting the content-type and charset is obviously a good practice, doing it on the server is much better, because it ensures consistency across your application.
However, I would use UTF-8 only when the language of my application uses a lot of characters that are available only in the UTF-8 charset. If you want to show a unicode character or symbol in one of cases, you can do so without changing the charset of your page.
HTML renderers have always been able to display symbols which are not part of the encoding character set of the page, as long as you mention the symbol in its numeric character reference (NCR). Sounds weird but its true.
So, even if your html has a header that states it has an encoding of ansi or any of the iso charsets, you can display a check mark by using its html character reference, in decimal - ✓ or in hex - ✓
So its a little difficult to understand why you are facing this issue on your pages. Can you check if the NCR value is correct, this is a good reference http://www.fileformat.info/info/unicode/char/2713/index.htm
Make sure that you actually save the file as UTF-8, alternatively use HTML entities (&#nnn;) for the special characters.
Unlike proposed by Nicolas, the meta tag isn’t actually ignored by the browsers. However, the Content-Type HTTP header always has precedence over the presence of a meta tag in the document.
So make sure that you either send the correct encoding via the HTTP header, or don’t send this HTTP header at all (not recommended). The meta tag is mainly a fallback option for local documents which aren’t sent via HTTP traffic.
Using HTML entities should also be considered a workaround – that’s tiptoeing around the real problem. Configuring the web server properly prevents a lot of nuisance.
I think this is a file problem, you simple saved your file in 1-byte encoding like latin-1. Google up your editor and how to set files to utf-8.
I wonder why there are editors that don't default to utf-8.