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<!--
* @Author: OBKoro1
* @Github: https://github.com/OBKoro1
* @Description: web worker博客演示denmo,博客链接:https://juejin.im/user/58714f0eb123db4a2eb95372/posts
-->
<!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>
<div>打开控制台看输出</div>
</body>
</html>
class webWorker {
/**
* @description: webworker的简单封装
* @param {String} data js的url/script的id或class
* @param {Object} type 默认值给出,同页面的web worker传个’worker‘即可
* @return: WebWorker 对象
*/
constructor(data, type = "url") {
this.worker = null;
this.workerInit(data, type);
}
workerInit(data, type) {
if (type === "url") {
// 默认是以url脚本形式的worker线程
// 此时的data应该是一个url链接
this.worker = new Worker(data);
} else {
// 以字符串形式创建worker线程,把代码字符串,转成二进制对象,生成 URL,加载URL
const blob = new Blob([data]);
const url = window.URL.createObjectURL(blob);
this.worker = new Worker(url); // 加载
}
}
/**
* @description: 给worker线程发送消息
* @param {*} data 要发送的数据
*/
postMessage(data) {
return this.worker.postMessage(data);
}
/**
* @description: worker线程发送给主进程的数据
* @param {Function} fn 把数据通过回调的形式传出去
*/
onmessage(fn) {
this.worker.onmessage = msg => {
return fn(msg.data);
};
}
// 主线程关闭worker线程
closeWorker() {
return this.worker.terminate();
}
/**
* @description: 主线程监听worker线程的错误信息
* @param {Function} fn 错误信息回调
*/
errMsg(fn) {
this.worker.onerror = e => {
return fn(e);
};
}
}
const data = `
// worker线程加载脚本 TODO: Worker 线程无法读取本地文件,加载的脚本必须来自网络
// importScripts('hello1.js', 'http~.js');
// 监听主线程传过来的信息
self.onmessage = e => {
console.log('主线程传来的信息:', e.data);
// do something
};
// 发送信息给主线程
self.postMessage('来自worker线程');
// 关闭worker线程
function closeSon() {
return self.close();
}`;
const worker = new webWorker(data, "script");
worker.onmessage(data => {
console.log("父进程接收的数据:", data);
});
worker.postMessage("主进程传给worker线程");
worker.errMsg(msg => {
console.log("worker线程报错:", msg);
});
Also see: Tab Triggers