SharedWorker()

The SharedWorker() constructor creates a SharedWorker object that executes the script at the specified URL. This script must obey the same-origin policy.

If the URL has an invalid syntax or if the same-origin policy is violated, a DOMException of type SECURITY_ERR is thrown.

Syntax

var myWorker = new SharedWorker(aURL, options);

Parameters

aURL

A DOMString representing the URL of the script the worker will execute. It must obey the same-origin policy.

options Optional

An object containing option properties that can set when creating the object instance. Available properties are as follows:

• type: A DOMString specifying the type of worker to create. The value can be classic or module. If not specified, the default used is classic.
• credentials: A DOMString specifying the type of credentials to use for the worker. The value can be omit, same-origin, or include. If not specified, or if type is classic, the default used is omit (no credentials required).
• name: A DOMString specifying an identifying name for the SharedWorkerGlobalScope representing the scope of the worker, which is mainly useful for debugging purposes.

Return value

The created worker

Exceptions

• SecurityError is raised if the document is not allowed to start workers
• NetworkError is raised if the MIME type of one of the script is text/csv, image/*, video/*, or audio/*. It should always be text/javascript.
• SyntaxError is raised if aURL cannot be parsed.

Example

The following code snippet shows creation of a SharedWorker object using the SharedWorker() constructor and subsequent usage of the object:

var myWorker = new SharedWorker('worker.js');
myWorker.port.start();
first.onchange = function() {
  myWorker.port.postMessage([first.value,second.value]);
  console.log('Message posted to worker');
}
second.onchange = function() {
  myWorker.port.postMessage([first.value,second.value]);
  console.log('Message posted to worker');
}
myWorker.port.onmessage = function(e) {
  result1.textContent = e.data;
  console.log('Message received from worker');
}

For a full example, see our Basic shared worker example (run shared worker.)

Specifications

Browser compatibility

See also

• The SharedWorker interface it belongs to.