How to check in JavaScript if XMLHttpRequest object supports W3C Progress Events?

Question

Is there any way to check within JavaScript if XMLHttpRequest object supports W3C Progress Events? I mean here if setting onload, onprogress, onabort, onerror, etc. properties to some handler function would have those function called those events, as described.

Additional (bonus) question: is there a way to augment XMLHttpRequest (e.g. using some timers) to support those events?

Sidenote: I have first found about W3C Progress Events in the context of XMLHttpRequest here

Answer 1

Have you tried doing it this way?

try {
    var xhr = new XMLHttpRequest();

    if (xhr.onload !== undefined) {
        // Browser supports W3C Progress Events
    } else {
        // Browser does not support W3C Progress Events
    }
} catch (e) {
    // Browser is IE6 or 7
}

I tested this in Firefox & IE8. Firefox shows it supports it. IE says it has no support for W3C Progress events.