<!DOCTYPE html><html lang="en"><head><meta charset="UTF-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta http-equiv="X-UA-Compatible" content="ie=edge"><title>Document</title><style>*{margin: 0;padding: 0;list-style: none;}.box{height: 15px;margin-top: 20px;transform: translateX(-100%);transition: all 1s linear;}button{margin-top: 30px;}</style></head><body><div class="box"></div><div class="box"></div><div class="box"></div><div class="box"></div><button id="btn">点击开始</button><script>const box=document.querySelectorAll(".box")box.forEach((item,index)=>{item.style.cssText=`width:${100+index*15}px;background:rgb(${Math.random()*255},${Math.random()*255},${Math.random()*255})`}) btn.onclick=async function(){ for(let i=0;i<box.length;i++){ await fn(box[i]) } } function fn(el){ return new Promise((resolve,reject)=>{ el.style.transform=`translateX(0)`; el.addEventListener("transitionend",function(){ resolve();//为什么调用这个成功函数 }) }) } </script></body></html>新闻热点
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