How do I convert Word smart quotes and em dashes in a string?

问题

I have a form with a textarea. Users enter a block of text which is stored in a database.

Occasionally a user will paste text from Word containing smart quotes or emdashes. Those characters appear in the database as: –, ’, “ ,â€

What function should I call on the input string to convert smart quotes to regular quotes and emdashes to regular dashes?

I am working in PHP.

Update: Thanks for all of the great responses so far. The page on Joel's site about encodings is very informative: http://www.joelonsoftware.com/articles/Unicode.html

Some notes on my environment:

The MySQL database is using UTF-8 encoding. Likewise, the HTML pages that display the content are using UTF-8 (Update:) by explicitly setting the meta content-type.

On those pages the smart quotes and emdashes appear as a diamond with question mark.

Solution:

Thanks again for the responses. The solution was twofold:

1. Make sure the database and HTML files were explicitly set to use UTF-8 encoding.
2. Use htmlspecialchars() instead of htmlentities().

回答1:

This sounds like a Unicode issue. Joel Spolsky has a good jumping off point on the topic: http://www.joelonsoftware.com/articles/Unicode.html

回答2:

The mysql database is using UTF-8 encoding. Likewise, the html pages that display the content are using UTF-8.

The content of the HTML can be in UTF-8, yes, but are you explicitly setting the content type (encoding) of your HTML pages (generated via PHP?) to UTF-8 as well? Try returning a Content-Type header of "text/html;charset=utf-8" or add <meta> tags to your HTMLs:

<meta http-equiv="Content-Type" content="text/html;charset=utf-8"/>

That way, the content type of the data submitted to PHP will also be the same.

I had a similar issue and adding the <meta> tag worked for me.

回答3:

It sounds like the real problem is that your database is not using the same character encoding as your page (which should probably be UTF-8). In that case, if any user submits a non-ASCII character you'll probably see weird characters in the database. Finding and fixing just a few of them (curly quotes and em dashes) isn't going to solve the real problem.

Here is some info on migrating your database to another character encoding, at least for a MySQL database.

回答4:

This is an unfortunately all-too-common problem, not helped by PHP's very poor handling of character sets.

What we do is force the text through iconv

// Convert input data to UTF8, ignore any odd (MS Word..) chars
// that don't translate
$input = iconv("ISO-8859-1","UTF-8//IGNORE",$input);

The //IGNORE flag means that anything that can't be translated will be thrown away.

If you append the string //IGNORE, characters that cannot be represented in the target charset are silently discarded.

回答5:

We would often use standard string replace functions for that. Even though the nature of ASCII/Unicode in that context is pretty murky, it works. Just make sure your php file is saved in the right encoding format, etc.

回答6:

In my experience, it's easier to just accept the smart quotes and make sure you're using the same encoding everywhere. To start, add this to your form tag: accept-charset="utf-8"

回答7:

You could try mb_ convert_encoding from ISO-8859-1 to UTF-8.

$str = mb_convert_encoding($str, 'UTF-8', 'ISO-8859-1');

This assumes you want UTF-8, and convert can find reasonable replacements... if not, mb_str_replace or preg_replace them yourself.

回答8:

You have to be sure your database connection is configured to accept and provide UTF-8 from and to the client (otherwise it will convert to the "default", which is usually latin1).

In practice this means running a query SET NAMES 'utf8';

http://www.phpwact.org/php/i18n/utf-8/mysql

Also, smart quotes are part of the windows-1252 character set, not iso-8859-1 (latin-1). Not very relevant to your problem, but just FYI. The euro symbol is in there as well.

回答9:

the problem is on the mysql charset, I fixed my issues with this line of code.

mysql_set_charset('utf8',$link); 

回答10:

You have to manually change the collation of individual columns to UTF8; changing the database overall won't alter these.

回答11:

If you were looking to escape these characters for the web while preserving their appearance, so your strings will appear like this: “It’s nice!” rather than "It's boring"...

You can do this by using your own custom htmlEncode function in place of PHP's htmlentities():

$trans_tbl = false;

function htmlEncode($text) {

  global $trans_tbl;

  // create translation table once
  if(!$trans_tbl) {
    // start with the default set of conversions and add more.

    $trans_tbl = get_html_translation_table(HTML_ENTITIES); 

    $trans_tbl[chr(130)] = '‚';    // Single Low-9 Quotation Mark
    $trans_tbl[chr(131)] = 'ƒ';    // Latin Small Letter F With Hook
    $trans_tbl[chr(132)] = '„';    // Double Low-9 Quotation Mark
    $trans_tbl[chr(133)] = '…';    // Horizontal Ellipsis
    $trans_tbl[chr(134)] = '†';    // Dagger
    $trans_tbl[chr(135)] = '‡';    // Double Dagger
    $trans_tbl[chr(136)] = 'ˆ';    // Modifier Letter Circumflex Accent
    $trans_tbl[chr(137)] = '‰';    // Per Mille Sign
    $trans_tbl[chr(138)] = 'Š';    // Latin Capital Letter S With Caron
    $trans_tbl[chr(139)] = '‹';    // Single Left-Pointing Angle Quotation Mark
    $trans_tbl[chr(140)] = 'Œ';    // Latin Capital Ligature OE

    // smart single/ double quotes (from MS)
    $trans_tbl[chr(145)] = '‘'; 
    $trans_tbl[chr(146)] = '’'; 
    $trans_tbl[chr(147)] = '“'; 
    $trans_tbl[chr(148)] = '”'; 

    $trans_tbl[chr(149)] = '•';    // Bullet
    $trans_tbl[chr(150)] = '–';    // En Dash
    $trans_tbl[chr(151)] = '—';    // Em Dash
    $trans_tbl[chr(152)] = '˜';    // Small Tilde
    $trans_tbl[chr(153)] = '™';    // Trade Mark Sign
    $trans_tbl[chr(154)] = 'š';    // Latin Small Letter S With Caron
    $trans_tbl[chr(155)] = '›';    // Single Right-Pointing Angle Quotation Mark
    $trans_tbl[chr(156)] = 'œ';    // Latin Small Ligature OE
    $trans_tbl[chr(159)] = 'Ÿ';    // Latin Capital Letter Y With Diaeresis

    ksort($trans_tbl);
  }

  // escape HTML      
  return strtr($text, $trans_tbl); 
}

回答12:

This may not be the best solution, but I'd try testing to find out what PHP sees. Let's say it sees "–" (there are a few other possibilities, like simple "“" or maybe "“"). Then do a str_replace to get rid of all of those and replace them with normal quotes, before stuffing the answer in a database.

The better solution would probably involve making the end-to-end data passing all UTF-8, as people are trying to help with in other answers.

回答13:

Actually the problem is not happening in PHP but it is happening in JavaScript, it is due to copy/paste from Word, so you need to solve your problem in JavaScript before you pass your text to PHP, Please see this answer https://stackoverflow.com/a/6219023/1857295.

来源：https://stackoverflow.com/questions/175785/how-do-i-convert-word-smart-quotes-and-em-dashes-in-a-string