mounted () {  var boDiv = document.getElementById(this.id);  if(boDiv == undefined){  return;  }  var isFirefox=navigator.userAgent.indexOf("Firefox")   if(isFirefox>0){   boDiv.addEventListener('DOMMouseScroll', function(event) { //火狐   var evt = window.event || arguments[0]   if (evt.detail <= -3) {    boDiv.scrollTop=boDiv.scrollTop-10   } else if (evt.detail >= 3) {   boDiv.scrollTop=boDiv.scrollTop+10   }   evt.stopPropagation();   evt.preventDefault();  }, false);   }else{  boDiv.addEventListener("mousewheel",function(event) {   var evt = window.event || arguments[0]   evt.returnValue = false //屏蔽body滾動事件    if (evt.wheelDelta <= -120) {    boDiv.scrollTop=boDiv.scrollTop+40   } else if (evt.wheelDelta >= 120) {   boDiv.scrollTop=boDiv.scrollTop-40   }  })  }  } }