worker在Typescript的使用

业务需求是在前端显示报表，但是sharepoint online无法直接用数据库，只能调REST API在前端显示

一、内嵌worker

       此方法优点是浏览器不用每次去加载你所写的worker.js

 this.domElement.innerHTML=`
Worker 花费时间: 

    开始 Worker 
开始主线程
原花费时间: 


//插入的worker
`;

下面通过新建worker来调用，

var blob = new Blob([document.querySelector('#worker1').textContent]);
    const worker = new Worker(window.URL.createObjectURL(blob));
    worker.addEventListener('message', message => {
        document.getElementById('result').innerHTML=message.data;
    });
    this.domElement.getElementsByTagName('button').item(0).addEventListener('click',function(){
      worker.postMessage(c);
    })

二、调用外部worker.js文件

编写js文件

var a;
function groupBy(array, f) {
    debugger;
    const groups = {};
    array.forEach(function (o) {
        const group = JSON.stringify(f(o));
        groups[group] = groups[group] || [];
        groups[group].push(o);
    });
    return Object.keys(groups).map(function (group) {
        return groups[group];
    });
  }
addEventListener('message', (message) => {
    var status;
    var st = new Date();
    var xLabel=[],ylabel=[];
        groupBy(message.data,(t)=>{
            return t.country
        }).forEach(function(e){
           xLabel.push(e[0].country);
           var sum=0;
           e.forEach(element => {
               sum+=element.cost;
           });
           ylabel.push(sum);
        })
       
    status = (new Date().getTime() - st.getTime()) + ' ms';
  
 
    postMessage("time :"+status) ;
});

声明file-loaderfile-loader把js加载到服务器此文件为file-loader.d.ts文件，typescript会进行编译根据此js加载

declare module "file-loader?name=[name].js!*" {
    const value: string;
    export = value;
}

声明创建worker

import * as workerPath from "file-loader?name=[name].js!./test.worker";
const worker = new Worker(workerPath);

console.log(workerPath, worker);
worker.addEventListener('message', message => {
    console.log(message);
});
worker.postMessage('this is a test message to the worker');