---
title: "events.beforeUpload Property  HTML5/Flash Uploader JavaScript"
canonical: https://www.aurigma.com/docs/us8/FH_P_J_$au_events_beforeUpload.htm
product: "Upload Suite 8"
---

# events.beforeUpload Property HTML5/Flash Uploader JavaScript

Supported technologies: ![Adobe Flash](https://www.aurigma.com/docs/us8/icons/flash.png)![HTML 5](https://www.aurigma.com/docs/us8/icons/html5.png)
 
Gets or sets an array of **BeforeUpload** event handlers.

## Syntax
 
```
$au.imageUploaderFlash({
    events: {
        //...other params...
        beforeUpload: [],
        //...other params...
    }
})
```

```
$au.imageUploaderFlash('uploaderID').events().beforeUpload(value);
value = $au.imageUploaderFlash('uploaderID').events().beforeUpload();
```
 
### Property Value
 
Type: [$au.event](https://www.aurigma.com/docs/us8/FH_T_J_$au_event.htm.md)
 
The string containing the name of **BeforeUpload** event handler or an array of handler names.

## Remarks
 
This event fires when the upload is about to be started.
 
### Returns
 
A boolean value (`true` or `false`). If event handler returns `false` (or zero), the upload is cancelled. Otherwise, upload begins immediately after the event handler finishes. This makes the event handler convenient for validating additional data provided by user.

## See Also
 
### Reference
 
- [ClientEvents.BeforeUpload PHP Property HTML5/Flash Uploader](https://www.aurigma.com/docs/us8/FH_P_P_ClientEvents_BeforeUpload.htm.md)

### Manual
 
- [Using HTML5/Flash Uploader at Runtime](https://www.aurigma.com/docs/us8/using-image-uploader-flash-at-runtime.htm.md)