AbortSignal.md

AbortSignal

Namespace: SpawnDev.SpawnJS.JSObjects
Inherits: EventTarget
Source: JSObjects/AbortSignal.cs
MDN Reference: AbortSignal on MDN

The AbortSignal interface represents a signal object that allows you to communicate with a DOM request (such as a fetch request) and abort it if required via an AbortController object. https://developer.mozilla.org/en-US/docs/Web/API/AbortSignal

Constructors

Signature	Description
AbortSignal(SpawnJSObjectReference _ref)	Deserialization constructor

Properties

Property	Type	Access	Description
Aborted	bool	get	A Boolean that indicates whether the request(s) the signal is communicating with is/are aborted (true) or not (false).
Reason	SpawnJSObject?	get	A JavaScript value providing the abort reason, once the signal has aborted.

Methods

Method	Return Type	Description
GetReason()	T	A JavaScript value providing the abort reason, once the signal has aborted. Type to read the property reason as
ThrowIfAborted()	void	Throws the signal's abort reason if the signal has been aborted; otherwise it does nothing.
Abort()	AbortSignal	The AbortSignal.abort() static method returns an AbortSignal that is already set as aborted (and which does not trigger an abort event).
Abort(object reason)	AbortSignal	The AbortSignal.abort() static method returns an AbortSignal that is already set as aborted (and which does not trigger an abort event). The reason why the operation was aborted, which can be any JavaScript value. If not specified, the reason is set to "AbortError" DOMException.
Timeout(float time)	AbortSignal	The AbortSignal.timeout() static method returns an AbortSignal that will automatically abort after a specified time. The "active" time in milliseconds before the returned AbortSignal will abort. An AbortSignal.
Any(Array<AbortSignal> signals)	AbortSignal	Returns an AbortSignal that aborts when any of the given abort signals abort. An AbortSignal that is: - Already aborted, if any of the abort signals given is already aborted. The returned AbortSignal's reason will be already set to the reason of the first abort signal that was already aborted. - Asynchronously aborted, when any abort signal in iterable aborts. The reason will be set to the reason of the first abort signal that is aborted.

Events

Event	Type	Description
OnAbort	ActionEvent<Event>	Invoked when the asynchronous operations the signal is communicating with is/are aborted. Also available via the onabort property.

Examples

SpawnDev.SpawnJS Mapping Note: The JavaScript examples below show the standard Web API usage. In SpawnDev.SpawnJS, the same API is available with C# conventions:

• Properties and methods use PascalCase (e.g., readyState becomes ReadyState)
• Events use ActionEvent with +=/-= (e.g., addEventListener("click", fn) becomes OnClick += handler)
• Async methods return Task<T> instead of Promise<T>
• Objects should be disposed with using statements
• Access via JS.Get<AbortSignal>(...) or constructor new AbortSignal(...)

Aborting a fetch operation using an explicit signal

let controller;
const url = "video.mp4";

const downloadBtn = document.querySelector(".download");
const abortBtn = document.querySelector(".abort");

downloadBtn.addEventListener("click", fetchVideo);

abortBtn.addEventListener("click", () => {
  if (controller) {
    controller.abort();
    console.log("Download aborted");
  }
});

async function fetchVideo() {
  controller = new AbortController();
  const signal = controller.signal;

  try {
    const response = await fetch(url, { signal });
    console.log("Download complete", response);
    // process response further
  } catch (err) {
    console.error(`Download error: ${err.message}`);
  }
}

Aborting a fetch operation using an explicit signal

async function get() {
  const controller = new AbortController();
  const request = new Request("https://example.org/get", {
    signal: controller.signal,
  });

  const response = await fetch(request);
  controller.abort();
  // The next line will throw `AbortError`
  const text = await response.text();
  console.log(text);
}

Aborting a fetch operation with a timeout

const url = "video.mp4";

try {
  const res = await fetch(url, { signal: AbortSignal.timeout(5000) });
  const result = await res.blob();
  // …
} catch (err) {
  if (err.name === "TimeoutError") {
    console.error("Timeout: It took more than 5 seconds to get the result!");
  } else if (err.name === "AbortError") {
    console.error(
      "Fetch aborted by user action (browser stop button, closing tab, etc.)",
    );
  } else {
    // A network error, or some other problem.
    console.error(`Error: type: ${err.name}, message: ${err.message}`);
  }
}

See full example on MDN