关于定时器的小应用

  <!DOCTYPE html>
  <html lang="en">
  <head>
  <meta charset="UTF-8">
  <title>定时器练习</title>
   
  <style type="text/css">
  #div1{
  width: 100px;
  height: 100px;
  background: #666;
  margin-top: 20px;
  position: absolute;
  left: 0;
  }
   
   
  </style>
  <script type="text/javascript">
  window.onload=function(){
  var oBtn=document.getElementById('btn1');
  var oBtn1=document.getElementById('btn2');
  var oDiv=document.getElementById('div1');
  var timer=null;
   
  oBtn.onclick=function(){
  move(oDiv,19,500);
  }
   
  oBtn1.onclick=function(){
  move(oDiv,-10,0);
  }
   
  function move(obj,speed,iTarget){
  clearInterval(timer)
  timer=setInterval(function(){
  var long=oDiv.offsetLeft+speed;
  if(long>=iTarget&&speed>0){
  long=iTarget
  }
  if(long<=iTarget&&speed<0){
  long=iTarget
  }
  oDiv.style.left=long+'px';
   
  if(parseInt(oDiv.style.left)<=0){
  oDiv.style.left=0
  }
  },30)
  }
  }
  </script>
  </head>
  <body>
  <button id="btn2">向左</button>
  <button id="btn1">向右</button>
   
  <div id="div1">
   
  </div>
  </body>
  </html>

         在线测试地址:http://codepen.io/itguy/pen/vGMpdg

posted @ 2016-05-18 10:57  小全栈  阅读(120)  评论(0编辑  收藏  举报