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

type

A string with the name of the event. It is case-sensitive and browsers set it to loadstart, progress, abort, error, load, timeout, or loadend.

options Optional

An object that, in addition of the properties defined in Event(), can have the following properties:

lengthComputable Optional

A boolean value indicating if the total work to be done, and the amount of work already done, by the underlying process is calculable. In other words, it tells if the progress is measurable or not. It defaults to false.

loaded Optional

A number 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. It defaults to 0.

total Optional

A number 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. It defaults to 0.

A new ProgressEvent object.

• The ProgressEvent interface it belongs to.