onloadstart event
ProgressEvent that occurs when a read operation is started by an MSStreamReader or FileReader object.
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Syntax
| Event Property | object.onloadstart = handler; |
|---|---|
| addEventListener Method | object.addEventListener("loadstart", handler, useCapture) |
Event handler parameters
- handler [in]
-
Type: function
Handler function to process the loadstart event.
Remarks
This event will always fire after a read method is successfully called on an MSStreamReader or FileReader object and before any other events are fired by the objects for the read operation.
When this event fires, the lengthComputable property of the ProgressEvent is initialized to false. The length property of the ProgressEvent is initialized to 0 (zero) and the total property is initialized to 0 (zero).
See also
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