Is PHP serialize function compatible UTF-8?

Question

I have a site I want to migrate from ISO to UTF-8.

I have a record in database indexed by the following primary key :

s:22:"Informations générales";

The problem is, now (with UTF-8), when I serialize the string, I get :

s:24:"Informations générales";

(notice the size of the string is now the number of bytes, not string length)

So this is not compatible with non-utf8 previous records !

Did I do something wrong ? How could I fix this ?

Thanks

Answer 1

The behaviour is completely correct. Two strings with different encodings will generate different byte streams, thus different serialization strings.

Answer 2

Dump the database in latin1.

In the command line:

sed  -e 's/latin1/utf8/g' -i ./DBNAME.sql

Import the file converted to a new database in UTF-8.

Use a php script to update each field. Make a query, loop through each field and update the serialized string using this:

$str = preg_replace('!s:(\d+):"(.*?)";!se', "'s:'.strlen('$2').':\"$2\";'", $str);

After that, I was able to use unserialize() and everything working with UTF-8.