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The loadstart event is fired when progress has begun on the loading of a resource. This applies for example to XMLHttpRequest calls, and to the content of an <img> or <video> element.

General info

HTMLImageElement, for example
Default Action


Property Type Description
target Read only EventTarget The event target (the topmost target in the DOM tree).
type Read only DOMString The type of event.
bubbles Read only Boolean Whether the event normally bubbles or not.
cancelable Read only Boolean Whether the event is cancellable or not.
lengthComputable Read only Boolean Specifies whether or not the total size of the transfer is known. Read only.
loaded Read only unsigned long (long) The number of bytes transferred since the beginning of the operation. This doesn't include headers and other overhead, but only the content itself. Read only.
total Read only unsigned long (long) The total number of bytes of content that will be transferred during the operation. If the total size is unknown, this value is zero. Read only.

See also

Document Tags and Contributors

Contributors to this page: fscholz, Sebastianz, chrisdavidmills, teoli, Sheppy, ethertank, louisremi
Last updated by: fscholz,