PHP Slug URL不能用于utf-8字符

Question

我需要使用此PHP函数（我从wordpress formatting.php中选择此函数）来插入我的UTF-8网址字符：

function sanitize_title_with_dashes( $title, $raw_title = '') {
    $title = strip_tags($title);
    // Preserve escaped octets.
    $title = preg_replace('|%([a-fA-F0-9][a-fA-F0-9])|', '---$1---', $title);
    // Remove percent signs that are not part of an octet.
    $title = str_replace('%', '', $title);
    // Restore octets.
    $title = preg_replace('|---([a-fA-F0-9][a-fA-F0-9])---|', '%$1', $title);

    if (seems_utf8($title)) {
        if (function_exists('mb_strtolower')) {
            $title = mb_strtolower($title, 'UTF-8');
        }
        $title = utf8_uri_encode($title, 200);
    }

    $title = strtolower($title);
    $title = preg_replace('/&.+?;/', '', $title); // kill entities
    $title = str_replace('.', '-', $title);


    $title = preg_replace('/[^%a-z0-9 _-]/', '', $title);
    $title = preg_replace('/\s+/', '-', $title);
    $title = preg_replace('|-+|', '-', $title);
    $title = trim($title, '-');

    return $title;
}
function seems_utf8( $str ) {
    mbstring_binary_safe_encoding();
    $length = strlen($str);
    reset_mbstring_encoding();
    for ($i=0; $i < $length; $i++) {
        $c = ord($str[$i]);
        if ($c < 0x80) $n = 0; // 0bbbbbbb
        elseif (($c & 0xE0) == 0xC0) $n=1; // 110bbbbb
        elseif (($c & 0xF0) == 0xE0) $n=2; // 1110bbbb
        elseif (($c & 0xF8) == 0xF0) $n=3; // 11110bbb
        elseif (($c & 0xFC) == 0xF8) $n=4; // 111110bb
        elseif (($c & 0xFE) == 0xFC) $n=5; // 1111110b
        else return false; // Does not match any model
        for ($j=0; $j<$n; $j++) { // n bytes matching 10bbbbbb follow ?
            if ((++$i == $length) || ((ord($str[$i]) & 0xC0) != 0x80))
                return false;
        }
    }
    return true;
}
function utf8_uri_encode( $utf8_string, $length = 0 ) {
    $unicode = '';
    $values = array();
    $num_octets = 1;
    $unicode_length = 0;

    mbstring_binary_safe_encoding();
    $string_length = strlen( $utf8_string );
    reset_mbstring_encoding();

    for ($i = 0; $i < $string_length; $i++ ) {

        $value = ord( $utf8_string[ $i ] );

        if ( $value < 128 ) {
            if ( $length && ( $unicode_length >= $length ) )
                break;
            $unicode .= chr($value);
            $unicode_length++;
        } else {
            if ( count( $values ) == 0 ) {
                if ( $value < 224 ) {
                    $num_octets = 2;
                } elseif ( $value < 240 ) {
                    $num_octets = 3;
                } else {
                    $num_octets = 4;
                }
            }

            $values[] = $value;

            if ( $length && ( $unicode_length + ($num_octets * 3) ) > $length )
                break;
            if ( count( $values ) == $num_octets ) {
                for ( $j = 0; $j < $num_octets; $j++ ) {
                    $unicode .= '%' . dechex( $values[ $j ] );
                }

                $unicode_length += $num_octets * 3;

                $values = array();
                $num_octets = 1;
            }
        }
    }

    return $unicode;
}
function mbstring_binary_safe_encoding( $reset = false ) {
    static $encodings = array();
    static $overloaded = null;

    if ( is_null( $overloaded ) )
        $overloaded = function_exists( 'mb_internal_encoding' ) && ( ini_get( 'mbstring.func_overload' ) & 2 );

    if ( false === $overloaded )
        return;

    if ( ! $reset ) {
        $encoding = mb_internal_encoding();
        array_push( $encodings, $encoding );
        mb_internal_encoding( 'ISO-8859-1' );
    }

    if ( $reset && $encodings ) {
        $encoding = array_pop( $encodings );
        mb_internal_encoding( $encoding );
    }
}
function reset_mbstring_encoding() {
    mbstring_binary_safe_encoding( true );
}

in action对于带破折号的show url，我尝试：

header('Content-type: text/plain; charset=utf-8');
echo sanitize_title_with_dashes('برای تست ارسال می شد');

但在输出中我看到：

%d8%a8%d8%b1%d8%a7%db%8c-%d8%aa%d8%b3%d8%aa-%d8%a7%d8%b1%d8%b3%d8%a7%d9%84-%d9%85%db%8c-%d8%b4%d8%af

我该如何解决这个问题？！