渲染一万条数据不卡住页面 - 《JavaScript》

<!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>
</head>
<body>
 <ul>控件</ul>
 <script>
    setTimeout(() => {
       // 插入十万条数据
      const total = 100000
      // 一次插入 20 条，如果觉得性能不好就减少
      const once = 20
      // 渲染数据总共需要几次
     const loopCount = total / once
      let countOfRender = 0
      let ul = document.querySelector("ul");
      function add() {
      // 优化性能，插入不会造成回流
       const fragment = document.createDocumentFragment();
      for (let i = 0; i < once; i++) {
        const li = document.createElement("li");
        li.innerText = Math.floor(Math.random() * total);
        fragment.appendChild(li);
      }
     ul.appendChild(fragment);
     countOfRender += 1;
     loop();
  }
  function loop() {
      if (countOfRender < loopCount) {
       window.requestAnimationFrame(add);
   }
  }
  loop();
  }, 0);
 </script>
</body>
</html>