XMLHttpRequest Level 2 events: equivlents to readyState

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XMLHttpRequest Level 2 adds a number of more meaningful events over the onreadystatechange one.

Is there a correspondence between some of these events and the readyState values?

As far as I can tell:

1   loadstart
2   progress
3   ?
4   loadend; load

I haven’t worked out equivalent for 3, which is a bit vague anyway.

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Jaromanda X On

Here's what I observe using the following code:

var oReq = new XMLHttpRequest();

oReq.addEventListener("progress", ev);
oReq.addEventListener("load", ev);
oReq.addEventListener("loadstart", ev);
oReq.addEventListener("loadend", ev);
oReq.addEventListener("readystatechange", ev);


oReq.open('GET', '/blah');

function ev(e) {
    console.log(e.type, oReq.readyState);
}
oReq.send();

Output result

readystatechange 1
loadstart 1
readystatechange 2
readystatechange 3
progress 3
readystatechange 4
load 4
loadend 4

so it seems it is

  1. loadstart
  2. ??? - no equivalent - (which is headers received)
  3. progress
  4. load/loadend