javascript - 如何增加向上滚动的计数

Question

我必须在每个滚动条上增加计数 1。例如:

let scrollCount = 0;
//initially it would be 0 and after  every scroll up it should increase 1,
scrollCount++;

react-native中每次滚动时递增计数1的函数是什么。

//下面的js代码我知道..但是对于react-native来说会很困惑。

var scrollCount = 0;
           window.addEventListener('mousewheel', function(e){

            if(e.wheelDelta<=0 && scrollCount<5){
            scrollCount++;
            }

          else if(e.wheelDelta>0 && scrollCount>1){
        scrollCount--;
        }
         document.querySelector('.number').innerHTML = scrollCount;
         });

Answer 1

object.onscroll = function(){
  //myScript
};

每次滚动时运行脚本

或添加事件监听器:

object.addEventListener("scroll", myScript);

就变成这样了:

var scrollCount = 0;
//object is your document. or any DOM element you would like to add
object.onscroll = function(){
  scrollCount++;
};