function animate(obj, json, interval, sp, fn) {
?clearInterval(obj.timer);
?//var k = 0;
?//var j = 0;
?function getStyle(obj, arr) {
???if(obj.currentStyle){
?????return obj.currentStyle[arr]; ?//针对ie
???} else {
?????return document.defaultView.getComputedStyle(obj, null)[arr];
???}
?}
?obj.timer = setInterval(function(){
???//j ++;
???var flag = true;
???for(var arr in json) {
?????var icur = 0;
?????//k++;
?????if(arr == "opacity") {
???????icur = Math.round(parseFloat(getStyle(obj, arr))*100);
?????} else {
???????icur = parseInt(getStyle(obj, arr));
?????}
?????var speed = (json[arr] - icur) * sp;
?????speed = speed > 0 ? Math.ceil(speed): Math.floor(speed);
?????if(icur != json[arr]){
???????flag = false;
?????}
?????if(arr == "opacity"){
???????obj.style.filter = "alpha(opacity : ‘+(icur + speed)+‘ )";
???????obj.style.opacity = (icur + speed)/100;
?????}else {
???????obj.style[arr] = icur + speed + "px";
?????}
?????//console.log(j + "," + arr +":"+ flag);
???}
???if(flag){
?????clearInterval(obj.timer);
?????//console.log(j + ":" + flag);
?????//console.log("k = " + k);
?????//console.log("j = " + j);
?????//console.log("DONE");
?????if(fn){
???????fn();
?????}
???}
?},interval);
}
JS封装运动框架（另一种写法）
原文地址：http://www.cnblogs.com/dragon126/p/7658350.html