XMLHttpRequest: load event
Baseline Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
当一个XMLHttpRequest
请求完成的时候会触发load
事件。
Bubbles | No |
---|---|
Cancelable | No |
Interface | ProgressEvent |
Event handler property | onload |
示例
在线示例
HTML
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>
JS
js
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("dgszyjnxcaipwzy.jpg");
});
xhrButtonError.addEventListener("click", () => {
runXHR("https://somewhere.org/i-dont-exist");
});
xhrButtonAbort.addEventListener("click", () => {
runXHR("dgszyjnxcaipwzy.jpg").abort();
});
结果
规范
Specification |
---|
XMLHttpRequest Standard # event-xhr-load |
XMLHttpRequest Standard # handler-xhr-onload |
浏览器兼容性
BCD tables only load in the browser