public function DKIM_QP($txt)
    {
        $line = '';
        $len = strlen($txt);
        for ($i = 0; $i < $len; ++$i) {
            $ord = ord($txt[$i]);
            if (((0x21 <= $ord) and ($ord <= 0x3A)) or $ord == 0x3C or ((0x3E <= $ord) and ($ord <= 0x7E))) {
                $line .= $txt[$i];
            } else {
                $line .= '=' . sprintf('%02X', $ord);
            }
        }

        return $line;
    }
public function DKIM_QP($txt)
    {
        $line = '';
        $len = strlen($txt);
        for ($i = 0; $i < $len; ++$i) {
            $ord = ord($txt[$i]);
            if (((0x21 <= $ord) and ($ord <= 0x3A)) or $ord == 0x3C or ((0x3E <= $ord) and ($ord <= 0x7E))) {
                $line .= $txt[$i];
            } else {
                $line .= '=' . sprintf('%02X', $ord);
            }
        }

        return $line;
    }
public function DKIM_QP ( $ txt ) { $ line = '' ; $ len = strlen ( $ txt ) ; for ( $ i = 0 ; $ i < $ len ; ++ $ i ) { $ ord = ord ( $ txt [ $ i ] ) ; if ( ( ( 0x21 <= $ ord ) and ( $ ord <= 0x3A ) ) or $ ord == 0x3C or ( ( 0x3E <= $ ord ) and ( $ ord <= 0x7E ) ) ) { $ line .= $ txt [ $ i ] ; } else { $ line .= '=' . sprintf ( '%02X' , $ ord ) ; } } return $ line ; }
Quoted-Printable-encode a DKIM header.

@param string $txt

@return string
Quoted - Printable - encode a DKIM header .