This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
Note: This feature is available in Web Workers.
The ProgressEvent.total read-only property is a number indicating the total size of the data being transmitted or processed.
For ProgressEvents dispatched by the browser, the value refers to the size, in bytes, of a resource and is derived from the Content-Length response header.
In a ProgressEvent you create yourself, this may also be the total bytes of a resource, although this can be any number. For example, you may wish to normalize total to a value such as 100 or 1 if revealing the precise amount of bytes of a resource is a concern. If using 1 as a total, then ProgressEvent.loaded would be a decimal value between 0 and 1.
If the event's lengthComputable property is false, this value is meaningless and should be ignored.
A number.
| Specification |
|---|
| XMLHttpRequest> # dom-progressevent-total> |
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
total |
1 | 12 | 3.5 | ≤12.1 | 3.1 | 18 | 4 | ≤12.1 | 2 | 1.0 | 4.4 | 2 |
ProgressEvent interface it belongs to.
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https://developer.mozilla.org/en-US/docs/Web/API/ProgressEvent/total