PHP UTF-8 handling

Question

I am parsing a text file and am occassionally running into data such as:

CASTA¥EDA, JASON  

Using a Mongo DB backend when I try saving information, I am getting errors like:

[MongoDB\Driver\Exception\UnexpectedValueException]
  Got invalid UTF-8 value serializing 'Jason Casta�eda'

After Googling a few places, I located two functions that the author says would work:

 function is_utf8( $str )
    {
        return preg_match( "/^(
         [\x09\x0A\x0D\x20-\x7E]            # ASCII
       | [\xC2-\xDF][\x80-\xBF]             # non-overlong 2-byte
       |  \xE0[\xA0-\xBF][\x80-\xBF]        # excluding overlongs
       | [\xE1-\xEC\xEE\xEF][\x80-\xBF]{2}  # straight 3-byte
       |  \xED[\x80-\x9F][\x80-\xBF]        # excluding surrogates
       |  \xF0[\x90-\xBF][\x80-\xBF]{2}     # planes 1-3
       | [\xF1-\xF3][\x80-\xBF]{3}          # planes 4-15
       |  \xF4[\x80-\x8F][\x80-\xBF]{2}     # plane 16
      )*$/x",
            $str
        );
    }

    public function force_utf8($str, $inputEnc='WINDOWS-1252')
    {
        if ( $this->is_utf8( $str ) ) // Nothing to do.
            return $str;

        if ( strtoupper( $inputEnc ) === 'ISO-8859-1' )
            return utf8_encode( $str );

        if ( function_exists( 'mb_convert_encoding' ) )
            return mb_convert_encoding( $str, 'UTF-8', $inputEnc );

        if ( function_exists( 'iconv' ) )
            return iconv( $inputEnc, 'UTF-8', $str );

        // You could also just return the original string.
        trigger_error(
            'Cannot convert string to UTF-8 in file '
            . __FILE__ . ', line ' . __LINE__ . '!',
            E_USER_ERROR
        );
    }

Using the two functions above I am trying to determine if a line of text has UTF-8 by calling is_utf8($text) and if it is not then I call the force_utf8($text) function. However I am getting the same error. Any pointers?

Answer 1

This question is pretty old, but for those who face same issue and get on this page like me:

mb_convert_encoding($value, 'UTF-8', 'UTF-8');

This code should replace all non UTF-8 characters by ? symbol and it will be safe for MongoDB insert/update operations.