本文实例讲述了js实现带按钮的上下滚动效果。分享给大家供大家参考。具体实现方法如下：
<!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>js带按钮上下滚动效果</title> <style type="text/css"> ul{ margin:0; padding:0; list-style:none; height:100000px; } li{ margin:0; padding:0; width:100px; height:100px; display:block; float:top; margin-bottom:5px; background:#009900; } #img_bag{ width:110px; height:600px; background:#F2F2F2; margin:0 auto; text-align:center; } #img_bag #img{ width:100px; height:525px; background:#969696; overflow:hidden; margin:auto; } </style> </head> <body> <div id="img_bag"> <a href="javascript:void(0)" onmousedown="moveTop()"> <img src="upp.jpg" border="0" /></a> <div id="img"> <ul> <li>1</li> <li>2</li> <li>3</li> <li>4</li> <li>5</li> <li>6</li> <li>7</li> <li>8</li> <li>9</li> <li>10</li> <li>11</li> <li>12</li> </ul> </div> <a href="javascript:void(0)" onmousedown="moveBottom()"> <img src="down.jpg" border="0" /></a> </div> <script type="text/javascript"> function $(obj){ //获取指定对象 return document.getElementById(obj); } var maxHeight=$("img").getElementsByTagName("ul")[0].getElementsByTagName("li").length*105; //滚动图片的最大高度 var targety = 211; //一次滚动距离 var dx; var a=null; function moveTop(){ var le=parseInt($("img").scrollTop); if(le>211){ targety=parseInt($("img").scrollTop)-211; }else{ targety=parseInt($("img").scrollTop)-le-1; } scTop(); } function scTop(){ dx=parseInt($("img").scrollTop)-targety; $("img").scrollTop-=dx*.3; clearScroll=setTimeout(scTop,50); if(dx*.3<1){ clearTimeout(clearScroll); } } function moveBottom(){ var le=parseInt($("img").scrollTop)+211; var maxL=maxHeight-600; if(le<maxL){ targety=parseInt($("img").scrollTop)+211; }else{ targety=maxL } scBottom(); } function scBottom(){ dx=targety-parseInt($("img").scrollTop); $("img").scrollTop+=dx*.3; a=setTimeout(scBottom,50); if(dx*.3<1){ clearTimeout(a) } } </script> </body> </html>
运行效果如下所示：
希望本文所述对大家的javascript程序设计有所帮助。