Sending data to a Web Worker

Now that we've seen how to send messages back and forth, we can start to actually put these Web Workers to work. In this recipe, we'll see that you can send data to and from a Web Worker.

Getting ready

This recipe assumes you already have a workspace that allows you to create and run ES modules in your browser. If you don't, please see the first two chapters.

How to do it...

1. Open your command-line application and navigate to your workspace.
2. Create a new folder named 05-03-send-data-to-and-from-web-workers.
3. Copy or create an index.html that loads and runs a main function from main.js.
4. Create a main.js with a function named onMessage that takes an argument message and logs out the type and index properties:

// main.js 
function onMessage(message) { 
  const { result, type } = message.data; 
  console.log('Result for operation (%s): (%s)', type, result); 
}  

5. Create a main function that creates a worker, sets the onMessage property, creates an array of random numbers, and...