XMLHttpRequest.upload

The XMLHttpRequest.upload property returns an XMLHttpRequestUpload object, representing the upload process. It is an opaque object, but being an XMLHttpRequestEventTarget, event listeners can be set on it to track its process.

Event listeners that can be triggered on an upload object are the following:

Event listeners	Data type of response property
onloadstart	The fetch starts
onprogress	Data transfer is going on
onabort	The fetch operation was aborted
onerror	The fetch failed
onload	The fetch succeeded
ontimeout	The fetch operation didn't complete by the timeout the author specified
onloadend	The fetch operation completed (either success or failure)

Specifications

Specification	Status	Comment
XMLHttpRequest	Living Standard	WHATWG living standard

Browser compatibility