javascript countdown timer with start & stop buttons

Question

I need to make a simple countdown timer from 5 to zero, with the buttons to START and STOP the counter. The only thing that I don\'t know is that why won\'t my counter stop.

Answer 1

This solution worked for me in react JS

let Timer =(function(){
    let timerObject;
    let callback=null;
    let seconds=0;
    let counter=()=>{
        seconds++;
        console.log("seconds",seconds);
        if (callback!==undefined) callback(seconds);
    }
    let setCallback=(_callback)=>{callback=_callback }
    let getSeconds=()=>{ return seconds;}
    let reset=()=>{ seconds=0;}
    let start=()=>{timerObject=setInterval(counter,1000);}
    let end=()=>{clearInterval(timerObject);}
    return {"start":start,"end":end, "getSeconds":getSeconds, "reset":reset,"setCallback":setCallback}; })();

export default Timer;