public static function voice($code = null)
    {
        $sms = new self();
        $sms->type(self::TYPE_VOICE);
        $sms->code($code);

        return $sms;
    }
public static function voice($code = null)
    {
        $sms = new self();
        $sms->type(self::TYPE_VOICE);
        $sms->code($code);

        return $sms;
    }
public static function voice ( $ code = null ) { $ sms = new self ( ) ; $ sms -> type ( self :: TYPE_VOICE ) ; $ sms -> code ( $ code ) ; return $ sms ; }
Create a instance for send voice.

@param int|string|null $code

@return Sms
Create a instance for send voice .