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web api event

XMLHttpRequestEventTarget: loadend event

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Available in workers

The loadend event is fired when a request has completed, whether successfully (after load) or unsuccessfully (after abort or error).

Syntax

Use the event name in methods like addEventListener(), or set an event handler property.

addEventListener("loadend", (event) => { })

onloadend = (event) => { }

Event type

A ProgressEvent. Inherits from Event.

Examples

Usage with XMLHttpRequest

HTML

<div class="controls">
  <input
    class="xhr success"
    type="button"
    name="xhr"
    value="Click to start XHR (success)" />
  <input
    class="xhr error"
    type="button"
    name="xhr"
    value="Click to start XHR (error)" />
  <input
    class="xhr abort"
    type="button"
    name="xhr"
    value="Click to start XHR (abort)" />
</div>

<textarea readonly class="event-log"></textarea>
.event-log {
  width: 25rem;
  height: 4rem;
  border: 1px solid black;
  margin: 0.5rem;
  padding: 0.2rem;
}

input {
  width: 11rem;
  margin: 0.5rem;
}

JavaScript

const xhrButtonSuccess = document.querySelector(".xhr.success");
const xhrButtonError = document.querySelector(".xhr.error");
const xhrButtonAbort = document.querySelector(".xhr.abort");
const log = document.querySelector(".event-log");

function handleEvent(e) {
  log.textContent = `${log.textContent}${e.type}: ${e.loaded} bytes transferred\n`;
}

function addListeners(xhr) {
  xhr.addEventListener("loadstart", handleEvent);
  xhr.addEventListener("load", handleEvent);
  xhr.addEventListener("loadend", handleEvent);
  xhr.addEventListener("progress", handleEvent);
  xhr.addEventListener("error", handleEvent);
  xhr.addEventListener("abort", handleEvent);
}

function runXHR(url) {
  log.textContent = "";

  const xhr = new XMLHttpRequest();
  addListeners(xhr);
  xhr.open("GET", url);
  xhr.send();
  return xhr;
}

xhrButtonSuccess.addEventListener("click", () => {
  runXHR(
    "https://raw.githubusercontent.com/mdn/content/main/files/en-us/_wikihistory.json",
  );
});

xhrButtonError.addEventListener("click", () => {
  runXHR("http://i-dont-exist");
});

xhrButtonAbort.addEventListener("click", () => {
  runXHR(
    "https://raw.githubusercontent.com/mdn/content/main/files/en-us/_wikihistory.json",
  ).abort();
});

Result

Interactive exampleOpen the canonical MDN source to run this embedded demo.

Usage with XMLHttpRequestUpload

You can use the loadend event to detect the (successful or not) termination of an upload. For a complete code example that uploads a file and displays a progress bar, see the main XMLHttpRequestUpload page.

// When the upload is finished, we hide the progress bar.
xhr.upload.addEventListener("loadend", (event) => {
  progressBar.classList.remove("visible");
  if (event.loaded !== 0) {
    // Successful termination
    log.textContent = "Upload finished.";
  }
  abortButton.disabled = true;
});

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also