PHP Array Key encoding?

Question

I use a encoded string as a key in array, and also uses the same string as a value in the array, like below code indicates:

$string = \'something in some enc         


        

Answer 1

I don't know if you can encode correctly string to use them as keys in an array, but even if it is possible to use such variables names :

• $élement = 'foo';
• $garçon = 'bar';

(note the ç and the é)

It is not recommended. You should not rely on this.

You would probably map with current english name or use indexes.

For utf8 encoding, take a look at the php manual.

Answer 2

I tried in Japanese (as is what I can test):

$test["要"]["name"] = "要";
print_r($test);

And the result went fine, as expected. I'm using UTF-8 for everything. I'm not sure if its a problem with your encoding settings (in php.ini) or the encoding you are using. if that is a problem, why don't you try to encode it with base64? (or other Ascii encoder). That way would be something like:

$test["6KaB"]["name"] = "要";

I'm not sure what is your goal, so let me know if it was useful.

Answer 3

Are you viewing it through your browser? Then you need to specify the encoding:

header('Content-Type: text/plain; charset=UTF-8'); // or BIG5, or whatever

Are you viewing it in your terminal? Make sure your terminal settings are set to that same encoding.

Answer 4

Just tried to enforce a collision, but it does not happen.

PHP Version 5.3.6 (Mac OS 10.7.5)

    $test["要"] = "要";

    for ($i=0;$i<5000000;$i++) {
        $key = "";
        $num = $i;
        while ($num != 0) {
            $ascii = $num % 256;
            $num = floor($num / 256);
            $key .= chr($ascii);
        }

        $test[$key] = 'boom';
        if ($test["要"] != 'boom') {
            unset($test[$key]);
        }   
    }

    print_r($test);

outputs:

    Array ( [要] => 要 )

no collision.

Answer 5

A key is of type integer or string.

To quote the manual

A string is series of characters. Before PHP 6, a character is the same as a byte. That is, there are exactly 256 different characters possible. This also implies that PHP has no native support of Unicode. See utf8_encode() and utf8_decode() for some basic Unicode functionality.

So it makes sense in your case to encode the string used as key (or only the key, depends on what you will do): utf8_encode()