js 取滚动条 和视口大小

    function getScrollSize(){
      if(window.pageXOffset){
        return {
          x:window.pageXOffset,
          y:window.pageYOffset
        }
      }else{
        return {
          x:document.body.offsetLeft+document.documentElement.offsetLeft,
          y:document.body.offsetTop+document.documentElement.offsetTop
        }
      }
    }
    function getViewPortSize(){
      if(window.innerWidth){
        return {
          w:window.innerWidth,
          h:window.innerHeight
        }
      }else{
        if(window.compatMode==='BackCompat'){
          return {
          w:document.body.clientWidth,
          h:document.body.clientHeight
        }
        }else{
          return {
            w:document.documentElement.clientWidth,
            h:document.documentElement.clientHeight
          }
        }
      }
    }

 

    function getDomStyle(ele,prop){
      if(window.getComputedStyle){
        return window.getComputedStyle(ele,null)[prop]
      }else{
        return ele.currentStyle[prop]
      }
    }

 

    function addDomEvent(ele, eventType, fun) {
      if (ele.addEventListener) {
        ele.addEventListener(eventType, fun, false)
      } else if (ele.attachEvent) {
        ele.attachEvent('on' + eventType, fun.call(ele))
      } else {
        ele['on' + eventType] = fun
      }
    }