The ProgressEvent.lengthComputable read-only property is a Boolean flag indicating if the resource concerned by the ProgressEvent has a length that can be calculated. If not, the ProgressEvent.total property has no significant value.

API Progress Events ProgressEvent Property

The ProgressEvent.loaded read-only property is an unsigned long long representing the amount of work already performed by the underlying process. The ratio of work done can be calculated with the property and ProgressEvent.total. When downloading a resource using HTTP, this only represent the part of the content itself, not headers and other overhead.

API Progress Event ProgressEvent Property

The ProgressEvent() constructor returns a newly created ProgressEvent, representing the current completion of a long process.

API Constructor DOM Events ProgressEvent

The ProgressEvent interface represents events measuring progress of an underlying process, like an HTTP request (for an XMLHttpRequest, or the loading of the underlying resource of an <img>, <audio>, <video>, <style> or <link>).

API Interface Progress Events ProgressEvent Reference

The ProgressEvent.initProgressEvent() method Initializes an animation event created using the deprecated Document.createEvent("ProgressEvent") method.

API Deprecated Method Progress Events ProgressEvent

The ProgressEvent.total read-only property is an unsigned long long representing the total amount of work that the underlying process is in the progress of performing. When downloading a resource using HTTP, this only represent the content itself, not headers and other overhead.

API Progress Event ProgressEvent Property Reference Référence