本文实例讲述了JavaScript缓冲运动实现方法。分享给大家供大家参考，具体如下：
实现原理：(目标距离-当前距离) / 基数 = 速度(运动距离越大速度越小，运动距离和速度成反比)复制代码 代码如下:(500 - oDiv.offsetLeft) / 7 = iSpeed;
需要注意：当计算出来的速度有小数时需要取整；
复制代码 代码如下:(500 - oDiv.offsetLeft) / 7 = iSpeed; iSpeed = iSpeed>0?Math.ceil(iSpeed):Math.floor(iSpeed);
例子1：滑块缓冲运动
<!doctype html> <html> <head> <meta charset="utf-8"> <title>缓冲运动</title> <style> #div1{ width:100px; height:100px; background:red; position:absolute; top:50px; left:0;} span{ width:1px; height:300px; background:black; position:absolute; left:300px; top:0; display:block;} </style> <script> window.onload = function() { var oBtn = document.getElementById('btn1'); var oDiv = document.getElementById('div1'); oBtn.onclick = function() { startMove(oDiv, 300); }; }; var timer = null; function startMove(obj, iTarget) { clearInterval(timer); timer = setInterval(function(){ var iSpeed = (iTarget - obj.offsetLeft)/8; iSpeed = iSpeed>0?Math.ceil(iSpeed):Math.floor(iSpeed); if(iTarget==obj.offsetLeft){ clearInterval(timer); }else{ obj.style.left = obj.offsetLeft + iSpeed + 'px'; } }, 30); } </script> </head> <body> <input id="btn1" type="button" value="移动" /> <div id="div1"></div> <span></span> </body> </html>
例子2：侧边栏滑动
<!doctype html> <html> <head> <meta charset="utf-8"> <title>侧边栏滑动</title> <style> #div1{ width:100px; height:100px; background:red; position:absolute; right:0; top:0;} </style> <script> window.onload = window.onscroll = function() { var oDiv = document.getElementById('div1'); var iScrollTop = document.documentElement.scrollTop || document.body.scrollTop; var clientHeight = document.documentElement.clientHeight; var iH = (clientHeight - oDiv.offsetHeight)/2 + iScrollTop; //oDiv.style.top = iH + 'px'; startMove(oDiv, parseInt(iH)); }; var timer = null; function startMove(obj, iTarget) { clearInterval(timer); timer = setInterval(function(){ var iSpeed = (iTarget - obj.offsetTop) / 8; iSpeed = iSpeed>0?Math.ceil(iSpeed):Math.floor(iSpeed); if(obj.offsetTop == iTarget){ clearInterval(timer); }else{ obj.style.top = obj.offsetTop + iSpeed + 'px'; } }, 30); } </script> </head> <body> <div id="div1"></div> </body> </html>
希望本文所述对大家JavaScript程序设计有所帮助。