防抖函数

function debounce(func, time) {    let timer = null;    return function () {      let context = this      // console.log('context :', this);      clearTimeout(timer)      timer = setTimeout(function () {        console.log('this :', this);        func.call(this)      }, time)    }  }复制代码

节流函数

function throttle(method, time) {    var timer = null;    var startTime = 0;    return function () {      var endTime = new Date();      var resTime = endTime - startTime;      //判断大于等于我们给的时间采取执行函数;      if (resTime >= time) {        method.call(this);        //执行完函数之后重置初始时间，等于最后一次触发的时间        startTime = endTime;      }    }  }复制代码

测试:

window.onscroll = debounce(() => {    console.log(1);  }, 500)  function fn() {    _throttle()  }  let _throttle = throttle(function () {    console.log(2);  }, 1000)  window.onmousemove = fn复制代码