JS-滚动条到底触发

window.onmousewheel = function(){
   var scrollT = document.body.scrollTop || document.documentElement.scrollTop //兼容处理
   currtTop = document.documentElement.clientHeight + scrollT
   console.log(document.body.scrollHeight);
   console.log(document.documentElement.clientHeight)
   if(currtTop >= document.body.scrollHeight){
      console.log('End')
   }
}