节流
什么是节流？
高频事件触发，但在 n 秒内只会执行一次，
所以节流会稀释函数的执行频率。
代码附上
<!-- 第一种方法 -->
<script>
function coloring() {
let r = Math.floor(Math.random()*255);
let g = Math.floor(Math.random()*255);
let b = Math.floor(Math.random()*255);
document.body.style.background = `rgb(${r},${g},${b})`;
}
function throttle(func,delay) {
let timer;
return function() {
let that = this;
let args = arguments;
if (timer) {
return;
}
timer = setTimeout(()=>{
func.apply(that,args);
timer = null;
},delay)
}
}
window.addEventListener('resize',throttle(coloring,2000));
</script>
<!-- 第二种 -->
<!-- <script>
function coloring() {
let r = Math.floor(Math.random()*255);
let g = Math.floor(Math.random()*255);
let b = Math.floor(Math.random()*255);
document.body.style.background = `rgb(${r},${g},${b})`;
}
function throttle(func,delay) {
let pro = 0;
return function() {
let now = new Date();
let that = this;
let args = arguments;
if (now - pro > delay) {
func.apply(that,args)
pro = now;
}
}
}
window.addEventListener('resize',throttle(coloring,2000));
</script> -->
