How To Give A Player A Effect On PlayerItemHeldEvent?

Ok So I Am Trying To Give A Player A Effecf On PlayerItemHeldEvent And It Dosent Work Here Is The Code

PHP:

if($item instanceof Item){
            switch($item->getId()){
                case 278:
                    $player->addEffect("10");
                break;
        }
        }

nevermind i got it!

addEffect must be passed with an Effect object. Also, you should never use strings for numbers unless you are playing with the bcadd() family functions (which most of us don't need to use it. I have never used it. It is only for processing extremely large numbers).

yeah i change that today cause it didnt wrk cause i didnt set the length and amp

Length and amplitude have default values if you don't set them.