Watch time javascript example

            <!DOCTYPE html>
<html>
<head>
<title>This is a page title</title>
</head>
<body>

<div class="well bg-whight">
  <p>watch time</p>
  <p id="stopwatch">00:00:00</p>
  <button onclick="startTimer()">Start</button>
  <button onclick="stopTimer()">Stop</button>
  <button onclick="resetTimer()">Reset</button>
</div>

<script type="text/javascript">

	var ch = false;
	var count = 0;
	function startTimer() {
	    ch = true;
	};
	function stopTimer() {
	    ch = false;
	}
	function resetTimer() {
	    count = 0;
	    ch = false;
	}

	window.setInterval(function(){

	  	if(ch){
	      	count++;
	  	}

	  	var date = new Date(0);
	  	date.setSeconds(count);
	  	var timeString = date.toISOString().substr(11, 8);

	  	document.getElementById('stopwatch').innerHTML = timeString;
	  
	}, 1000);

</script>
</body>
</html>
        

            
        