mb_check_encoding

(PHP 4 >= 4.4.3, PHP 5 >= 5.1.3)

mb_check_encoding — Check if the string is valid for the specified encoding

bool mb_check_encoding ([ string $var=NULL [, string $encoding=mb_internal_encoding() ]] )

Checks if the specified byte stream is valid for the specified encoding. It is useful to prevent so-called "Invalid Encoding Attack".

var: The byte stream to check. If it is omitted, this function checks all the input from the beginning of the request.
encoding: The expected encoding.

如果成功则返回 TRUE，失败则返回 FALSE。