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                <p id="first"></p>
<p id="second"></p>
<p id="third"></p>




                document.querySelector("#first").innerHTML = "First";

// second 中的内容在线程中计算后返回
const second = document.querySelector("#second");
if (window.Worker) {
  second.innerHTML = "...";
  // 工作线程脚本
  const str = `
onmessage = function(e) {
  const time = Math.random() * 3000
  // 模拟复杂计算
  setTimeout(() => {
    postMessage(\`Second \${time.toFixed(0)} ms, ID is \${}\`);
  }, time);
  const blob = new Blob([str]);
  const url = window.URL.createObjectURL(blob);
  // 加载 Worker 脚本
  this.worker = new Worker(url);
  // 发送消息
    uuid: new Date().getTime()
  // 接收消息
  worker.onmessage = function (e) {
    second.innerHTML =;
  // 错误事件
  worker.onerror = function (e) {
    second.innerHTML = "Error occured!";
} else {
  second.innerHTML = "Not supprot Web Worker!";

document.querySelector("#third").innerHTML = "Third";