代码如下：
<!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title></title> <style> *{ margin: 0; padding: 0; } #wrap{ width: 800px; height: 500px; border: 1px solid deeppink; margin-left: 10px; margin-top: 5px; float: left; } #input1{ width: 80px; margin: 5px auto 5px 10px; font-size: 0; float: left; } #div1{ width: 100px; height: 100px; background: hotpink; position: absolute; top: 20px; left: 30px; border-radius: 100px; box-shadow: 0px 5px 5px rgba(0,0,0,.5); } input{ width: 100px; height: 40px; line-height: 40px; text-align: center; font-size: 18px; display: block; background: palegreen; margin-bottom: 5px; } </style> </head> <body> <div> <div></div> </div> <div> <input type="button" value="向左" /> <input type="button" value="向右"/> <input type="button" value="向上" /> <input type="button" value="向下"/> </div> <script> var oBtn=document.getElementById('btn1'); var oDiv=document.getElementById('div1'); var oBtn2=document.getElementById('btn2'); var oBtn3=document.getElementById('btn3'); var oBtn4=document.getElementById('btn4'); oBtn4.onclick=function(){ move(oDiv,10,380,'0px 5px 5px rgba(0,0,0,.5)','top'); } oBtn3.onclick=function(){ move(oDiv,-10,30,'0px -5px 5px rgba(0,0,0,.5)','top'); } oBtn2.onclick=function(){ move(oDiv,-10,40,'-5px 5px 5px rgba(0,0,0,.5)','left'); } oBtn.onclick=function(){ move(oDiv,10,680,'5px 5px 5px rgba(0,0,0,.5)','left'); } function move(obj,val,target,bs,dir){ obj.style.boxShadow=bs; clearInterval(obj.timer); obj.timer=setInterval(function(){ var speed=parseInt(getStyle(obj,dir))+val; if(speed>=target&&val>0){ speed=target; } if(speed<=target&&val<0){ speed=target } obj.style[dir]=speed+'px'; if(speed==target){ clearInterval(obj.timer); } },30); } function getStyle(obj,sty){ return obj.currentStyle?obj.currentStyle[sty]:getComputedStyle(obj)[sty]; } </script> </body> </html>