转载：http://www.cnblogs.com/chenjt/p/4193464.html
主要用到dom.offsetWidth 这个表示实际的宽度。
dom.scrollLeft 这个表示这个容器dom的滚动条的水平偏移.
核心代码：
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>向上下左右不间断无缝滚动图片的效果(兼容火狐和IE)</title> </head> <body> <div id="colee" style="overflow:hidden;height:253px;410px;"> <div id="colee1"> <p><img src="http://www.le.com/favicon.ico"></p> <p><img src="http://www.le.com/favicon.ico"></p> <p><img src="http://www.le.com/favicon.ico"></p> <p><img src="http://www.le.com/favicon.ico"></p> <p><img src="http://www.le.com/favicon.ico"></p> <p><img src="http://www.le.com/favicon.ico"></p> <p><img src="http://www.le.com/favicon.ico"></p> <p><img src="http://www.le.com/favicon.ico"></p> </div> <div id="colee2"></div> </div> <script> var speed=30; var colee2=document.getElementById("colee2"); var colee1=document.getElementById("colee1"); var colee=document.getElementById("colee"); colee2.innerHTML=colee1.innerHTML; //克隆colee1为colee2 function Marquee1(){ //当滚动至colee1与colee2交界时 if(colee2.offsetTop-colee.scrollTop<=0){ colee.scrollTop-=colee1.offsetHeight; //colee跳到最顶端 }else{ colee.scrollTop++ } } var MyMar1=setInterval(Marquee1,speed)//设置定时器 //鼠标移上时清除定时器达到滚动停止的目的 colee.onmouseover=function() {clearInterval(MyMar1)} //鼠标移开时重设定时器 colee.onmouseout=function(){MyMar1=setInterval(Marquee1,speed)} </script> <!--向上滚动代码结束--> <br> <div style="height: 100px;background: pink;">这个上下之间的空白，</div> <!--下面是向下滚动代码--> <div id="colee_bottom" style="overflow:hidden;height:253px;410px;"> <div id="colee_bottom1"> <p><img src="http://www.le.com/favicon.ico"></p> <p><img src="http://www.le.com/favicon.ico"></p> <p><img src="http://www.le.com/favicon.ico"></p> <p><img src="http://www.le.com/favicon.ico"></p> <p><img src="http://www.le.com/favicon.ico"></p> <p><img src="http://www.le.com/favicon.ico"></p> <p><img src="http://www.le.com/favicon.ico"></p> <p><img src="http://www.le.com/favicon.ico"></p> <p><img src="http://www.le.com/favicon.ico"></p> </div> <div id="colee_bottom2"></div> </div> <script> var speed=30; var colee_bottom2=document.getElementById("colee_bottom2"); var colee_bottom1=document.getElementById("colee_bottom1"); var colee_bottom=document.getElementById("colee_bottom"); colee_bottom2.innerHTML=colee_bottom1.innerHTML colee_bottom.scrollTop=colee_bottom.scrollHeight function Marquee2(){ if(colee_bottom1.offsetTop-colee_bottom.scrollTop>=0) colee_bottom.scrollTop+=colee_bottom2.offsetHeight else{ colee_bottom.scrollTop-- } } var MyMar2=setInterval(Marquee2,speed) colee_bottom.onmouseover=function() {clearInterval(MyMar2)} colee_bottom.onmouseout=function() {MyMar2=setInterval(Marquee2,speed)} </script> <!--向下滚动代码结束--> <br> <!--下面是向左滚动代码--> <div id="colee_left" style="overflow:hidden;252px;"> <table cellpadding="0" cellspacing="0" border="0"> <tr><td id="colee_left1" valign="top" align="center"> <table cellpadding="2" cellspacing="0" border="0"> <tr align="center"> <td><p><img src="http://www.le.com/favicon.ico"></p></td> <td><p><img src="http://www.le.com/favicon.ico"></p></td> <td><p><img src="http://www.le.com/favicon.ico"></p></td> <td><p><img src="http://www.le.com/favicon.ico"></p></td> <td><p><img src="http://www.le.com/favicon.ico"></p></td> <td><p><img src="http://www.le.com/favicon.ico"></p></td> <td><p><img src="http://www.le.com/favicon.ico"></p></td> </tr> </table> </td> <td id="colee_left2" valign="top"></td> </tr> </table> </div> <script> //使用div时，请保证colee_left2与colee_left1是在同一行上. var speed=100;//速度数值越大速度越慢 var colee_left2=document.getElementById("colee_left2"); var colee_left1=document.getElementById("colee_left1"); var colee_left=document.getElementById("colee_left"); colee_left2.innerHTML=colee_left1.innerHTML function Marquee3(){ if(colee_left2.offsetWidth-colee_left.scrollLeft<=0){//offsetWidth 是对象的可见宽度 colee_left.scrollLeft-=colee_left1.offsetWidth//scrollWidth 是对象的实际内容的宽，不包边线宽度 } else{ colee_left.scrollLeft++; console.log("colee_left.scrollLeft"+colee_left.scrollLeft); } } var MyMar3=setInterval(Marquee3,speed) colee_left.onmouseover=function() {clearInterval(MyMar3)} colee_left.onmouseout=function() {MyMar3=setInterval(Marquee3,speed)} </script> <!--向左滚动代码结束--> <br> <!--下面是向右滚动代码--> <div id="colee_right" style="overflow:hidden;252px;"> <table cellpadding="0" cellspacing="0" border="0"> <tr><td id="colee_right1" valign="top" align="center"> <table cellpadding="2" cellspacing="0" border="0"> <tr align="center"> <td><p><img src="http://www.le.com/favicon.ico"></p></td> <td><p><img src="http://www.le.com/favicon.ico"></p></td> <td><p><img src="http://www.le.com/favicon.ico"></p></td> <td><p><img src="http://www.le.com/favicon.ico"></p></td> <td><p><img src="http://www.le.com/favicon.ico"></p></td> </tr> </table> </td> <td id="colee_right2" valign="top"></td> </tr> </table> </div> <script> var speed=30;//速度数值越大速度越慢 var colee_right2=document.getElementById("colee_right2"); var colee_right1=document.getElementById("colee_right1"); var colee_right=document.getElementById("colee_right"); colee_right2.innerHTML=colee_right1.innerHTML function Marquee4(){ if(colee_right.scrollLeft<=0) colee_right.scrollLeft+=colee_right2.offsetWidth else{ colee_right.scrollLeft-- } } var MyMar4=setInterval(Marquee4,speed) colee_right.onmouseover=function() {clearInterval(MyMar4)} colee_right.onmouseout=function() {MyMar4=setInterval(Marquee4,speed)} </script> <!--向右滚动代码结束--> </body> </html>
我自己写的发现向上没有使用offsetTop也行，反正原理都是等scrollTop和第一个的位移一样的时候，把scrollTop=0就行。
<!DOCTYPE html> <html> <head> <title></title> <style type="text/css"> *{margin:0;padding: 0} #yan>div>div{ display: inline-block; } #yan ul li { display: inline-block; } </style> </head> <body> <div id="yan" style="320px; overflow: hidden;"> <div style="644px; "> <div id="yan1"> <ul> <li><img src="http://www.le.com/favicon.ico"></li> <li><img src="http://www.le.com/favicon.ico"></li> <li><img src="http://www.le.com/favicon.ico"></li> <li><img src="http://www.le.com/favicon.ico"></li> <li><img src="http://www.le.com/favicon.ico"></li> <li><img src="http://www.le.com/favicon.ico"></li> <li><img src="http://www.le.com/favicon.ico"></li> <li><img src="http://www.le.com/favicon.ico"></li> <li><img src="http://www.le.com/favicon.ico"></li> </ul> </div> <div id="yan2"> </div> </div> </div> <hr/> <div id="shang" style="height:306px; overflow-y: hidden;"> <div style="height:612px; "> <div id="shang1"> <ul> <li><img src="http://www.le.com/favicon.ico"></li> <li><img src="http://www.le.com/favicon.ico"></li> <li><img src="http://www.le.com/favicon.ico"></li> <li><img src="http://www.le.com/favicon.ico"></li> <li><img src="http://www.le.com/favicon.ico"></li> <li><img src="http://www.le.com/favicon.ico"></li> <li><img src="http://www.le.com/favicon.ico"></li> <li><img src="http://www.le.com/favicon.ico"></li> <li><img src="http://www.le.com/favicon.ico"></li> </ul> </div> <div id="shang2"> </div> </div> </div> <script type="text/javascript"> var box1 = document.querySelector("#yan1"); var box2 = document.querySelector("#yan2"); var box = document.querySelector("#yan"); box2.innerHTML = box1.innerHTML; //向左 function left(){ if(box2.offsetWidth - box.scrollLeft <=0){ box.scrollLeft -= box1.offsetWidth; }else{ box.scrollLeft++; } } //向右 function right(){ if(box.scrollLeft <=0){ box.scrollLeft += box1.offsetWidth; }else{ box.scrollLeft--; } } //向上 /*function top(){ if(box.scrollLeft <=0){ box.scrollLeft += box1.offsetWidth; }else{ box.scrollLeft--; } }*/ var shang1 = document.querySelector("#shang1"); var shang2 = document.querySelector("#shang2"); var shang = document.querySelector("#shang"); shang2.innerHTML = shang1.innerHTML; shang.scrollTop = shang1.offsetHeight; //向下 function down(){ if(shang.scrollTop <=0){ shang.scrollTop+= shang1.offsetHeight; }else{ shang.scrollTop--; } } //向上 function up(){ if(shang1.offsetHeight - shang.scrollTop <=0){ shang.scrollTop -= shang1.offsetHeight; }else{ shang.scrollTop++; } } setInterval(up,20); </script> </body> </html>
这里我们需要知道offsetTop offsetHeight scrollTop的区别
1、scrollTop：https://developer.mozilla.org/en-US/docs/DOM/element.scrollTop
比较容易理解，一个可读写的属性
1）element.scrollTop 返回该元素当前垂直滚动的距离，比如100（无单位）
2）element.scrollTop = 100 将该元素垂直滚动的距离设置为100，注意100为绝对值，而不是相对值。比如当前元素垂直滚动距离 element.scrollTop = 200，则设置完后，该元素垂直滚动的距离为100，而不是100+200
2、offsetTop：https://developer.mozilla.org/en-US/docs/DOM/element.offsetTop
返回该元素相对于其offsetParent顶部的距离，至于offsetParent，指的是距离该元素最近的定位元素，如下所示
<div id="p"><a> <span id="c"></span> </a></div>， P为C的offsetParent，offsetTop则为C距离P顶部的距离
这里有一个写的比较简单的例子：
<<!DOCTYPE html> <html> <head> <title></title> <style type="text/css"> #marquee { position: relative; height: 300px; width: 200px; overflow: hidden; border: 10px solid #369; padding:0; margin:0; } #marquee img { display: block; } #marquee dd { margin: 0px; padding: 0px; } </style> </head> <body> <dl id="marquee"> <dt> <img src="http://images.cnblogs.com/cnblogs_com/rubylouvre/199042/o_s017.jpg" alt="无缝滚动" /> <img src="http://images.cnblogs.com/cnblogs_com/rubylouvre/199042/o_s018.jpg" alt="无缝滚动" /> <img src="http://images.cnblogs.com/cnblogs_com/rubylouvre/199042/o_s019.jpg" alt="无缝滚动" /> <img src="http://images.cnblogs.com/cnblogs_com/rubylouvre/199042/o_s020.jpg" alt="无缝滚动" /> <img src="http://images.cnblogs.com/cnblogs_com/rubylouvre/199042/o_s021.jpg" alt="无缝滚动" /> <img src="http://images.cnblogs.com/cnblogs_com/rubylouvre/199042/o_s022.jpg" alt="无缝滚动" /> <img src="http://images.cnblogs.com/cnblogs_com/rubylouvre/199042/o_s023.jpg" alt="无缝滚动" /> </dt> <dd> </dd> </dl> <script type="text/javascript"> var Marquee = function (id) { var container = document.getElementById(id), original = container.getElementsByTagName("dt")[0], clone = container.getElementsByTagName("dd")[0], speed = arguments[1] || 10; clone.innerHTML = original.innerHTML; alert(container.scrollTop); var rolling = function () { if (container.scrollTop == clone.offsetTop) { //我现在纠结的就是container.scrollTop和clone.offsetTop的区别 // 为什么clone.offsetTop是1050，而外面的container.scrollTop却是0 container.scrollTop = 0; } else { container.scrollTop++; } } var timer = setInterval(rolling, speed) container.onmouseover = function () { clearInterval(timer) } container.onmouseout = function () { timer = setInterval(rolling, speed) } } window.onload = function () { Marquee("marquee"); } </script> </body> </html>