如何在javascript字符串中处理UTF-8

Question

I have just upgraded from mysql 5.5 to 5.6 and the default encoding in version 5.6 is UTF-8.

All ajax requests are handled in UTF-8 too, so I decided to convert data in the database and the encoding on the website to UTF-8.

But now I'm experiencing a problem.. All special (unicode) chars on the website are displayed incorrect.. They are displayed as encoded UTF-8 strings (double bytes)

The whole site is build in 100% jquery, and all strings are provided by ajax requests and appended/written with jquery... I can't figure out what I'm doing wrong?!

Database connection

$dbh = new PDO($driver.':dbname='.$db.';host='.$host.';port='.$port.';charset=utf8', $user, $pass);

All tables and columns in the database is converted to UTF-8_bin

HTML encoding

header('Content-Type: text/html; charset=utf-8');
<meta charset="utf-8" />

The HTML page is encoded in UTF-8. Is both sending a header from PHP and have added a meta tag in the head in the HTML document

Ajax requests

header('Content-Type: application/json; charset=utf-8');
{
    type : 'post',
    async : true,
    cache : false,
    dataType : 'json',
    timeout : 15000,
    contentType : 'application/x-www-form-urlencoded;charset=utf-8',
    global : true,
    url : APIURL,
    data : {},
    success : function(){}
}

All Ajax requests is made with these properties

Ajax response

{"result":[{"id":"391","string":"BTN_ADD_ACCOUNTS","da":"Tilf\u00c3\u00b8j regnskab","en":"Add accounts"},{"id":"321","string":"BTN_ADD_ENTRY" ...

The value Tilf\Ã\¸j regnskab should be displayed as Tilføj regnskab on the page, but it is displayed as Tilføj regnskab

When browsing the database in phpmyadmin all data showed corretcly

I can put data in the database via Ajax requests and the data is stored correctly, but can't retrieve data via Ajax requests

update - db fetch

header('Content-Type: text/html; charset=utf-8');

$connect = $driver.':dbname='.$db.';host='.$host.';port='.$port.';charset=utf8';
$dbh = new PDO($connect, $user, $pass);
$dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
$sth = $dbh->prepare("SELECT da FROM lang WHERE string='HDL_CLIENT'");
$sth->execute();
$row = $sth->fetch(PDO::FETCH_ASSOC);
print_r($row);

// result
klient æå

Answer 1

I hadn't noticed the important bit. As icktoofay points out, your JSON is already corrupted:

>>> "Tilf\u00c3\u00b8j regnskab"
"Tilføj regnskab"

You have two characters ( \Ã\¸ ) to represent ø (which is obviously one character). Since ø is U+00F8 it should be just \ø :

>>> "Tilf\u00f8j regnskab"
"Tilføj regnskab"

The problem is in the PHP script that generates that JSON, not in the JavaScript code that consumes it. Possibilities:

• Your data is already corrupted at DB.
• Your data gets corrupted on fetch.

The UTF-8 representation for ø is "0xC3 0xB8 (c3b8)". To need to ensure that you see those bytes. To print hexadecimal values:

• MySQL - SELECT HEX(column_name) FROM table_name
• PHP - var_dump( bin2hex($variable) );