js定时器实例分享

setInterval(fn,1000)//正确setInterval(fn(),1000)//错误

window.onload = function() { var timer = null; var num = 0; var i = 0;  var arr=['red','#FF9D0C','#DBFF0D','#3BFF0D','#0DFFA2','#0DE8FF','#0D52FF','#210DFF','#930DFF','#FF0DB4'] var start = document.getElementById('start'); var stop = document.getElementById('stop'); var prizeDraw = document.getElementById('prizeDraw'); start.onclick = function() { clearInterval(timer); timer = setInterval(function(){  num = Math.floor(Math.random()*100+1); prizeDraw.style.backgroundColor = arr[i]; i++; if (i==9) { i = 0; }; prizeDraw.innerHTML = num; },100); } stop.onclick = function() { clearInterval(timer); }}

#prizeDraw { width: 100px; height: 100px; background: rgba(255,68,253,0.5); font-size: 30px; text-align: center; line-height: 100px; }

<div id="prizeDraw"></div> <input type="button" value="开始" id="start"> <input type="button" value="暂停" id="stop">