javascript 缓冲运动框架的实现

/**
 * Created by wang on 2016/8/3.
 */

//获取非行间样式和行间样式
function getStyle(obj,name) {
  if(obj.currentStyle){
    return obj.currentStyle[name];
  }
  else {
    return getComputedStyle(obj,false)[name];
  }
}
//获取非行间样式和行间样式

//缓冲运动框架
var timer=null;
function startMove(obj,attr,iTarget) {
  clearInterval(obj.timer);
  obj.timer=setInterval(function () {
    var cur=0;

    if(attr=='opacity'){
      cur=Math.round(parseFloat(getStyle(obj,attr))*100);
    }
    else {
      cur=parseInt(getStyle(obj,attr));
    }
    var speed=(iTarget-cur)/6;
    speed=speed>0?Math.ceil(speed):Math.floor(speed);
    if(cur==iTarget){
      clearInterval(timer);
    }
    else {
      if(attr=='opacity'){
        obj.style.filter='alpha(opcity:'+(cur+speed)+')';
        obj.style.opacity=(cur+speed)/100;
      }
      else {
        obj.style[attr]=cur+speed+'px';
      }
    }
  },30)
}
//缓冲运动框架