Question

I have a game that gives a time limit and I need to display a countdown clock for the users and stop the game once the time is up such as 30 seconds. How can I do this in javascript?

Answer 1

Use setInterval to set up a timer. Within this timer, you can update some text in your page and when the time is up, you can call whatever function you want:

var timeLeft = 30;
    var elem = document.getElementById('some_div');
    
    var timerId = setInterval(countdown, 1000);
    
    function countdown() {
      if (timeLeft == -1) {
        clearTimeout(timerId);
        doSomething();
      } else {
        elem.innerHTML = timeLeft + ' seconds remaining';
        timeLeft--;
      }
    }

<div id="some_div">
</div>