problem with mb_detect_encoding

[Marcus]

I am trying to determine if data entered in a $_POST variable in a form
contains all ASCII (0 - 127) characters or not. To do this I am using
mb_detect_encod ing(). I am running into problems with non-English
characters, however - for example, I translated the word 'test' into
Russian and got 'испытан ие'. If I feed this into the function as:

$_POST['var'] = 'испытан ие'; // from form
echo mb_detect_encod ing($_POST['var']);

it returns ASCII. After thinking about it and running some tests I
figured out that it is doing this because PHP is feeding
mb_detect_encod ing the string after it is converted to its html
representation, i.e. instead of 'испытан ие' mb_detect_encod ing() is
getting
'испытание' .
Obviously all of these characters are ASCII, and as far as I can tell
this is what's happening.

Is there a way that I can tell if data entered is ASCII or not BEFORE it
is converted? With the example above, I would want this test to fail
(not return ASCII). Thanks in advance.

[Tim Hunt]

Re: problem with mb_detect_encod ing


Marcus wrote:

I am trying to determine if data entered in a $_POST variable in a form
contains all ASCII (0 - 127) characters or not. To do this I am using
mb_detect_encod ing(). I am running into problems with non-English
characters, however - for example, I translated the word 'test' into
Russian and got 'испытан ие'.If I feed this into the function as:
>
$_POST['var'] = 'испытан ие'; // from form
echo mb_detect_encod ing($_POST['var']);
>
it returns ASCII. After thinking about it and running some tests I
figured out that it is doing this because PHP is feeding
mb_detect_encod ing the string after it is converted to its html
representation, i.e. instead of 'испытан ие' mb_detect_encod ing() is
getting
'испытание' .
Obviously all of these characters are ASCII, and as far as I can tell
this is what's happening.
>
Is there a way that I can tell if data entered is ASCII or not BEFORE it
is converted? With the example above, I would want this test to fail
(not return ASCII). Thanks in advance.

The form data is converted into html entities on the client side before
php receives the data, convert the html entities back into a string
using html_entity_dec ode()

Even then mb_detect_encod ings() might not work, the user notes in the
php manual aren't encouraging anyway. Someone gave a regular expression
for detecting utf-8 that can be adapted

I think preg_match( '/[^\x09\x0A\x0D\x 20-\x7E]/xs',
html_entity_dec ode($_POST['var']) ) will work

Tim Hunt