# htmx.on()
The `htmx.on()` function registers an event listener for htmx events.
## Syntax
```javascript
// Listen on document
htmx.on(event, callback)
// Listen on specific element
htmx.on(element, event, callback)
```
## Parameters
- `event` - Event name to listen for
- `callback` - Function to call when event fires
- `element` - Optional element to listen on (defaults to document)
## Example
```javascript
// Listen for all htmx requests
htmx.on('htmx:before:request', (evt) => {
console.log('Request starting:', evt.detail);
});
// Listen on specific element
htmx.on('#myForm', 'htmx:after:swap', (evt) => {
console.log('Form updated');
});
```
## Return Value
Returns the callback function, which can be used to remove the listener later.
Listen for htmx events
The htmx.on() function registers an event listener for htmx events.