Check string whether is UTF-8 or UCS-2

Question

If I have a list of data:

$a = "hello";

$b= "4f60";

$c = "hi";

$d = "00480065006C006C006F";

$b and $d are UCS-2 string. I wish to display all these data in a table,so how can I know whether which data is UCS-2 so that I can convert it before being displayed ? Is it possible ? I tried mb_detect_encoding and preg_match for unicode found at php.net , but even it is an unknown symbol it still considered as unicode.

Thank you.

Answer 1

First of all, the strings you show are hexadecimal representations, not the actual UCS-2 or UTF-8 encodings.

That said, there are some pretty huge differences between UCS-2 and UTF-8 that would allow you to write code that correctly detects the encoding with a really high success rate. But before doing that, show us how you are using mb_detect_encoding and it's not working. No sense in reinventing a worse wheel than already exists.

Update: Your input strings are not actually the encoded byte values; they are hex representations of the values. To undo this, you can use

$proper_string = pack('H*', $hex_encoded_string);

After this, mb_detect_encoding should work fine.