代码如下：
<!doctype html> <html> <head> <meta charset="UTF-8"> <title>Title</title> <style> *{margin:0; padding:0; list-style:none;} ul{ overflow:hidden; width:630px; margin:100px auto;} ul li{ float:left; position:relative; width:200px; height:200px; background:#ccc; margin:5px; overflow:hidden;} ul li span{ position:absolute; width:100%; height:100%; background:rgba(255,0,0,0.3); left:-200px; top:0;} </style> <script> function getStyle(obj,sName){ return (obj.currentStyle||getComputedStyle(obj,false))[sName]; } function move(obj,json,options){ options = options||{}; options.duration = options.duration||700; options.easing = options.easing||'ease-out'; var start = {}; var dis = {}; for(var name in json){ start[name] = parseFloat(getStyle(obj,name)); dis[name] = json[name]-start[name]; } var count = Math.floor(options.duration/30); var n = 0; clearInterval(obj.timer); obj.timer = setInterval(function(){ n++; for(var name in json){ switch(options.easing){ case 'linear': var cur = start[name]+dis[name]*n/count; break; case 'ease-in': var a = n/count; var cur = start[name]+dis[name]*Math.pow(a,3); break; case 'ease-out': var a = 1-n/count; var cur = start[name]+dis[name]*(1-Math.pow(a,3)); break; } if(name=='opacity'){ obj.style.opacity = cur; obj.style.filter = 'alpha(opacity:'+cur*100+')'; }else{ obj.style[name] = cur+'px'; } } if(n==count){ clearInterval(obj.timer); options.complete&&options.complete(); } },30); } function a2d(n){ return n*180/Math.PI; } function hoverDir(ev,obj){ var a = ev.clientX-obj.offsetLeft-obj.offsetWidth/2; var b = obj.offsetTop+obj.offsetHeight/2-ev.clientY; return Math.round((a2d(Math.atan2(b,a))+180)/90)%4; } function through(obj){ var oS = obj.children[0]; obj.onmouseenter = function(ev){ var oEvent = ev||event; var dir = hoverDir(oEvent,obj); switch(dir){ case 0: //左 oS.style.left = '-200px'; oS.style.top = 0; break; case 1: //下 oS.style.left = 0; oS.style.top = '200px'; break; case 2: //右 oS.style.left = '200px'; oS.style.top = 0; break; case 3: //上 oS.style.left = 0; oS.style.top = '-200px'; break; } move(oS,{left:0,top:0}); }; obj.onmouseleave = function(ev){ var oEvent = ev||event; var dir = hoverDir(oEvent,obj); switch(dir){ case 0: move(oS,{left:-200,top:0}); break; case 1: move(oS,{left:0,top:200}); break; case 2: move(oS,{left:200,top:0}); break; case 3: move(oS,{left:0,top:-200}); break; } }; } window.onload = function(){ var aLi = document.getElementsByTagName('li'); for(var i=0;i<aLi.length;i++){ through(aLi[i]); } }; </script> </head> <body> <ul> <li><span></span></li> <li><span></span></li> <li><span></span></li> <li><span></span></li> <li><span></span></li> <li><span></span></li> </ul> </body> </html>