+++
title = "Events"
+++
Htmx provides an extensive events system that can be used to modify and enhance behavior. Events
are listed below.
### Event - `htmx:abort` {#htmx:abort}
This event is different than other events: htmx does not *trigger* it, but rather *listens* for it.
If you send an `htmx:abort` event to an element making a request, it will abort the request:
```html
```
### Event - `htmx:afterOnLoad` {#htmx:afterOnLoad}
This event is triggered after an AJAX `onload` has finished. Note that this does not mean that the content
has been swapped or settled yet, only that the request has finished.
##### Details
* `detail.elt` - the element that dispatched the request or if the body no longer contains the element then the closest parent
* `detail.xhr` - the `XMLHttpRequest`
* `detail.target` - the target of the request
* `detail.requestConfig` - the configuration of the AJAX request
### Event - `htmx:afterProcessNode` {#htmx:afterProcessNode}
This event is triggered after htmx has initialized a DOM node. It can be useful for extensions to build additional features onto a node.
##### Details
* `detail.elt` - the element being initialized
### Event - `htmx:afterRequest` {#htmx:afterRequest}
This event is triggered after an AJAX request has finished either in the case of a successful request (although
one that may have returned a remote error code such as a `404`) or in a network error situation. This event
can be paired with [`htmx:beforeRequest`](#htmx:beforeRequest) to wrap behavior around a request cycle.
##### Details
* `detail.elt` - the element that dispatched the request or if the body no longer contains the element then the closest parent
* `detail.xhr` - the `XMLHttpRequest`
* `detail.target` - the target of the request
* `detail.requestConfig` - the configuration of the AJAX request
* `detail.successful` - true if the response has a 20x status code or is marked `detail.isError = false` in the
`htmx:beforeSwap` event, else false
* `detail.failed` - true if the response does not have a 20x status code or is marked `detail.isError = true` in the
`htmx:beforeSwap` event, else false
### Event - `htmx:afterSettle` {#htmx:afterSettle}
This event is triggered after the DOM has [settled](@/docs.md#request-operations).
##### Details
* `detail.elt` - the updated element
* `detail.xhr` - the `XMLHttpRequest`
* `detail.target` - the target of the request
* `detail.requestConfig` - the configuration of the AJAX request
### Event - `htmx:afterSwap` {#htmx:afterSwap}
This event is triggered after new content has been [swapped into the DOM](@/docs.md#swapping).
##### Details
* `detail.elt` - the swapped in element
* `detail.xhr` - the `XMLHttpRequest`
* `detail.target` - the target of the request
* `detail.requestConfig` - the configuration of the AJAX request
### Event - `htmx:beforeCleanupElement` {#htmx:beforeCleanupElement}
This event is triggered before htmx [disables](@/attributes/hx-disable.md) an element or removes it from the DOM.
##### Details
* `detail.elt` - the element to be cleaned up
### Event - `htmx:beforeOnLoad` {#htmx:beforeOnLoad}
This event is triggered before any response processing occurs. If you call `preventDefault()` on the event to cancel it, no swap will occur.
##### Details
* `detail.elt` - the element that dispatched the request
* `detail.xhr` - the `XMLHttpRequest`
* `detail.target` - the target of the request
* `detail.requestConfig` - the configuration of the AJAX request
### Event - `htmx:beforeProcessNode` {#htmx:beforeProcessNode}
This event is triggered before htmx initializes a DOM node and has processed all of its `hx-` attributes. This gives extensions and other external code the ability to modify the contents of a DOM node before it is processed.
##### Details
* `detail.elt` - the element being initialized
### Event - `htmx:beforeRequest` {#htmx:beforeRequest}
This event is triggered before an AJAX request is issued. If you call `preventDefault()` on the event to cancel it, no request will occur.
##### Details
* `detail.elt` - the element that dispatched the request
* `detail.xhr` - the `XMLHttpRequest`
* `detail.target` - the target of the request
* `detail.requestConfig` - the configuration of the AJAX request
### Event - `htmx:beforeSend` {#htmx:beforeSend}
This event is triggered right before a request is sent. You may not cancel the request with this event.
##### Details
* `detail.elt` - the element that dispatched the request
* `detail.xhr` - the `XMLHttpRequest`
* `detail.target` - the target of the request
* `detail.requestConfig` - the configuration of the AJAX request
### Event - `htmx:beforeSwap` {#htmx:beforeSwap}
This event is triggered before any new content has been [swapped into the DOM](@/docs.md#swapping). If you call `preventDefault()` on the event to cancel it, no swap will occur.
You can modify the default swap behavior by modifying the `shouldSwap` and `target` properties of the event detail. See
the documentation on [configuring swapping](@/docs.md#modifying_swapping_behavior_with_events) for more details.
##### Details
* `detail.elt` - the target of the swap
* `detail.xhr` - the `XMLHttpRequest`
* `detail.requestConfig` - the configuration of the AJAX request
* `detail.requestConfig.elt` - the element that dispatched the request
* `detail.shouldSwap` - if the content will be swapped (defaults to `false` for non-200 response codes)
* `detail.ignoreTitle` - if `true` any title tag in the response will be ignored
* `detail.target` - the target of the swap
### Event - `htmx:beforeTransition` {#htmx:beforeTransition}
This event is triggered before a [View Transition](https://developer.mozilla.org/en-US/docs/Web/API/View_Transitions_API)
wrapped swap occurs. If you call `preventDefault()` on the event to cancel it, the View Transition will not occur and the normal swapping logic will
happen instead.
##### Details
* `detail.elt` - the element that dispatched the request
* `detail.xhr` - the `XMLHttpRequest`
* `detail.requestConfig` - the configuration of the AJAX request
* `detail.shouldSwap` - if the content will be swapped (defaults to `false` for non-200 response codes)
* `detail.target` - the target of the swap
### Event - `htmx:configRequest` {#htmx:configRequest}
This event is triggered after htmx has collected parameters for inclusion in the request. It can be
used to include or update the parameters that htmx will send:
```javascript
document.body.addEventListener('htmx:configRequest', function(evt) {
evt.detail.parameters['auth_token'] = getAuthToken(); // add a new parameter into the mix
});
```
Note that if an input value appears more than once the value in the `parameters` object will be an array, rather
than a single value.
##### Details
* `detail.parameters` - the parameters that will be submitted in the request
* `detail.unfilteredParameters` - the parameters that were found before filtering by [`hx-params`](@/attributes/hx-params.md)
* `detail.headers` - the request headers
* `detail.elt` - the element that triggered the request
* `detail.target` - the target of the request
* `detail.verb` - the HTTP verb in use
### Event - `htmx:confirm` {#htmx:confirm}
This event is fired on every trigger for a request (not just on elements that have a hx-confirm attribute).
It allows you to cancel (or delay) issuing the AJAX request.
If you call `preventDefault()` on the event, it will not issue the given request.
The `detail` object contains a function, `evt.detail.issueRequest(skipConfirmation=false)`, that can be used to issue the actual AJAX request at a later point.
Combining these two features allows you to create an asynchronous confirmation dialog.
Here is a basic example that shows the basic usage of the `htmx:confirm` event without altering the default behavior:
```javascript
document.body.addEventListener('htmx:confirm', function(evt) {
// 0. To modify the behavior only for elements with the hx-confirm attribute,
// check if evt.detail.target.hasAttribute('hx-confirm')
// 1. Prevent the default behavior (this will prevent the request from being issued)
evt.preventDefault();
// 2. Do your own logic here
console.log(evt.detail)
// 3. Manually issue the request when you are ready
evt.detail.issueRequest(); // or evt.detail.issueRequest(true) to skip the built-in window.confirm()
});
```
And here is an example using [sweet alert](https://sweetalert.js.org/guides/) on any element with a `confirm-with-sweet-alert="{question}"` attribute on it:
```javascript
document.body.addEventListener('htmx:confirm', function(evt) {
// 1. The requirement to show the sweet alert is that the element has a confirm-with-sweet-alert
// attribute on it, if it doesn't we can return early and let the default behavior happen
if (!evt.detail.target.hasAttribute('confirm-with-sweet-alert')) return
// 2. Get the question from the attribute
const question = evt.detail.target.getAttribute('confirm-with-sweet-alert');
// 3. Prevent the default behavior (this will prevent the request from being issued)
evt.preventDefault();
// 4. Show the sweet alert
swal({
title: "Are you sure?",
text: question || "Are you sure you want to continue?",
icon: "warning",
buttons: true,
dangerMode: true,
}).then((confirmed) => {
if (confirmed) {
// 5. If the user confirms, we can manually issue the request
evt.detail.issueRequest(true); // true to skip the built-in window.confirm()
}
});
});
```
##### Details
* `detail.elt` - the element in question
* `detail.etc` - additional request information (mostly unused)
* `detail.issueRequest(skipConfirmation=false)` - a function that can be invoked to issue the request (should be paired with `evt.preventDefault()`!), if skipConfirmation is `true` the original `window.confirm()` is not executed
* `detail.path` - the path of the request
* `detail.target` - the element that triggered the request
* `detail.triggeringEvent` - the original event that triggered this request
* `detail.verb` - the verb of the request (e.g. `GET`)
* `detail.question` - the question passed to `hx-confirm` attribute (only available if `hx-confirm` attribute is present)
### Event - `htmx:historyCacheError` {#htmx:historyCacheError}
This event is triggered when an attempt to save the cache to `localStorage` fails
##### Details
* `detail.cause` - the `Exception` that was thrown when attempting to save history to `localStorage`
### Event - `htmx:historyCacheMiss` {#htmx:historyCacheMiss}
This event is triggered when a cache miss occurs when restoring history
##### Details
* `detail.xhr` - the `XMLHttpRequest` that will retrieve the remote content for restoration
* `detail.path` - the path and query of the page being restored
### Event - `htmx:historyCacheMissError` {#htmx:historyCacheMissError}
This event is triggered when a cache miss occurs and a response has been retrieved from the server
for the content to restore, but the response is an error (e.g. `404`)
##### Details
* `detail.xhr` - the `XMLHttpRequest`
* `detail.path` - the path and query of the page being restored
### Event - `htmx:historyCacheMissLoad` {#htmx:historyCacheMissLoad}
This event is triggered when a cache miss occurs and a response has been retrieved successfully from the server
for the content to restore
##### Details
* `detail.xhr` - the `XMLHttpRequest`
* `detail.path` - the path and query of the page being restored
### Event - `htmx:historyRestore` {#htmx:historyRestore}
This event is triggered when htmx handles a history restoration action
##### Details
* `detail.path` - the path and query of the page being restored
### Event - `htmx:beforeHistorySave` {#htmx:beforeHistorySave}
This event is triggered before the content is saved in the history api.
##### Details
* `detail.path` - the path and query of the page being restored
* `detail.historyElt` - the history element being restored into
##### Details
* `detail.config` - the config that will be passed to the `EventSource` constructor
### Event - `htmx:load` {#htmx:load}
This event is triggered when a new node is loaded into the DOM by htmx.
##### Details
* `detail.elt` - the newly added element
### Event - `htmx:noSSESourceError` {#htmx:noSSESourceError}
This event is triggered when an element refers to an SSE event in its trigger, but no parent SSE source has been defined
##### Details
* `detail.elt` - the element with the bad SSE trigger
### Event - `htmx:oobAfterSwap` {#htmx:oobAfterSwap}
This event is triggered as part of an [out of band swap](@/docs.md#oob_swaps) and behaves identically to an [after swap event](#htmx:afterSwap)
##### Details
* `detail.elt` - the swapped in element
* `detail.shouldSwap` - if the content will be swapped (defaults to `true`)
* `detail.target` - the target of the swap
* `detail.fragment` - the response fragment
### Event - `htmx:oobBeforeSwap` {#htmx:oobBeforeSwap}
This event is triggered as part of an [out of band swap](@/docs.md#oob_swaps) and behaves identically to a [before swap event](#htmx:beforeSwap)
##### Details
* `detail.elt` - the target of the swap
* `detail.shouldSwap` - if the content will be swapped (defaults to `true`)
* `detail.target` - the target of the swap
* `detail.fragment` - the response fragment
### Event - `htmx:oobErrorNoTarget` {#htmx:oobErrorNoTarget}
This event is triggered when an [out of band swap](@/docs.md#oob_swaps) does not have a corresponding element
in the DOM to switch with.
##### Details
* `detail.content` - the element with the bad oob `id`
### Event - `htmx:onLoadError` {#htmx:onLoadError}
This event is triggered when an error occurs during the `load` handling of an AJAX call
##### Details
* `detail.xhr` - the `XMLHttpRequest`
* `detail.elt` - the element that triggered the request
* `detail.target` - the target of the request
* `detail.exception` - the exception that occurred
* `detail.requestConfig` - the configuration of the AJAX request
### Event - `htmx:prompt` {#htmx:prompt}
This event is triggered after a prompt has been shown to the user with the [`hx-prompt`](@/attributes/hx-prompt.md)
attribute. If this event is cancelled, the AJAX request will not occur.
##### Details
* `detail.elt` - the element that triggered the request
* `detail.target` - the target of the request
* `detail.prompt` - the user response to the prompt
### Event - `htmx:beforeHistoryUpdate` {#htmx:beforeHistoryUpdate}
This event is triggered before a history update is performed. It can be
used to modify the `path` or `type` used to update the history.
##### Details
* `detail.history` - the `path` and `type` (push, replace) for the history update
* `detail.xhr` - the `XMLHttpRequest`
* `detail.target` - the target of the request
* `detail.requestConfig` - the configuration of the AJAX request
### Event - `htmx:pushedIntoHistory` {#htmx:pushedIntoHistory}
This event is triggered after a URL has been pushed into history.
##### Details
* `detail.path` - the path and query of the URL that has been pushed into history
### Event - `htmx:replacedInHistory` {#htmx:replacedInHistory}
This event is triggered after a URL has been replaced in history.
##### Details
* `detail.path` - the path and query of the URL that has been replaced in history
### Event - `htmx:responseError` {#htmx:responseError}
This event is triggered when an HTTP error response occurs
##### Details
* `detail.xhr` - the `XMLHttpRequest`
* `detail.elt` - the element that triggered the request
* `detail.target` - the target of the request
* `detail.requestConfig` - the configuration of the AJAX request
### Event - `htmx:sendAbort` {#htmx:sendAbort}
This event is triggered when a request is aborted
##### Details
* `detail.xhr` - the `XMLHttpRequest`
* `detail.elt` - the element that triggered the request
* `detail.target` - the target of the request
* `detail.requestConfig` - the configuration of the AJAX request
### Event - `htmx:sendError` {#htmx:sendError}
This event is triggered when a network error prevents an HTTP request from occurring
##### Details
* `detail.xhr` - the `XMLHttpRequest`
* `detail.elt` - the element that triggered the request
* `detail.target` - the target of the request
* `detail.requestConfig` - the configuration of the AJAX request
### Event - `htmx:sseError` {#htmx:sseError}
This event is triggered when an error occurs with an SSE source
##### Details
* `detail.elt` - the element with the bad SSE source
* `detail.error` - the error
* `detail.source` - the SSE source
### Event - `htmx:swapError` {#htmx:swapError}
This event is triggered when an error occurs during the swap phase
##### Details
* `detail.xhr` - the `XMLHttpRequest`
* `detail.elt` - the element that triggered the request
* `detail.target` - the target of the request
* `detail.requestConfig` - the configuration of the AJAX request
### Event - `htmx:targetError` {#htmx:targetError}
This event is triggered when a bad selector is used for a [`hx-target`](@/attributes/hx-target.md) attribute (e.g. an
element ID without a preceding `#`)
##### Details
* `detail.elt` - the element that triggered the request
* `detail.target` - the bad CSS selector
### Event - `htmx:timeout` {#htmx:timeout}
This event is triggered when a request timeout occurs. This wraps the typical `timeout` event of XMLHttpRequest.
Timeout time can be set using `htmx.config.timeout` or per element using [`hx-request`](@/attributes/hx-request.md)
##### Details
* `detail.elt` - the element that dispatched the request
* `detail.xhr` - the `XMLHttpRequest`
* `detail.target` - the target of the request
* `detail.requestConfig` - the configuration of the AJAX request
### Event - `htmx:trigger` {#htmx:trigger}
This event is triggered whenever an AJAX request would be, even if no AJAX request is specified. It
is primarily intended to allow `hx-trigger` to execute client-side scripts; AJAX requests have more
granular events available, like [`htmx:beforeRequest`](#htmx:beforeRequest) or [`htmx:afterRequest`](#htmx:afterRequest).
##### Details
* `detail.elt` - the element that triggered the request
### Event - `htmx:validateUrl` {#htmx:validateUrl}
This event is triggered before a request is made, allowing you to validate the URL that htmx is going to request. If
`preventDefault()` is invoked on the event, the request will not be made.
```javascript
document.body.addEventListener('htmx:validateUrl', function (evt) {
// only allow requests to the current server as well as myserver.com
if (!evt.detail.sameHost && evt.detail.url.hostname !== "myserver.com") {
evt.preventDefault();
}
});
```
##### Details
* `detail.elt` - the element that triggered the request
* `detail.url` - the URL Object representing the URL that a request will be sent to.
* `detail.sameHost` - will be `true` if the request is to the same host as the document
### Event - `htmx:validation:validate` {#htmx:validation:validate}
This event is triggered before an element is validated. It can be used with the `elt.setCustomValidity()` method
to implement custom validation rules.
```html
```
##### Details
* `detail.elt` - the element to be validated
### Event - `htmx:validation:failed` {#htmx:validation:failed}
This event is triggered when an element fails validation.
##### Details
* `detail.elt` - the element that failed validation
* `detail.message` - the validation error message
* `detail.validity` - the validity object, which contains properties specifying how validation failed
### Event - `htmx:validation:halted` {#htmx:validation:halted}
This event is triggered when a request is halted due to validation errors.
##### Details
* `detail.elt` - the element that triggered the request
* `detail.errors` - an array of error objects with the invalid elements and errors associated with them
### Event - `htmx:xhr:abort` {#htmx:xhr:abort}
This event is triggered when an ajax request aborts
##### Details
* `detail.elt` - the element that triggered the request
### Event - `htmx:xhr:loadstart` {#htmx:xhr:loadstart}
This event is triggered when an ajax request starts
##### Details
* `detail.elt` - the element that triggered the request
### Event - `htmx:xhr:loadend` {#htmx:xhr:loadend}
This event is triggered when an ajax request finishes
##### Details
* `detail.elt` - the element that triggered the request
### Event - `htmx:xhr:progress` {#htmx:xhr:progress}
This event is triggered periodically when an ajax request that supports progress is in flight
##### Details
* `detail.elt` - the element that triggered the request