Re-defining read-only JS methods

[sidki3003]

I'd like to accomplish below two changes in scripts:

Code:

Arbitrary_Object.userAgent

should become something equivalent to...

Code:

(Arbitrary_Object.PRXuserAgent || Arbitrary_Object.userAgent)

Code:

Arbitrary_Object.send(someArg)

should become something equivalent to...

Code:

if (Arbitrary_Object.setRequestHeader) Arbitrary_Object.setRequestHeader("X-Requested-With", "XMLHttpRequest");
Arbitrary_Object.send(someArg)

Probably the match has to be ".userAgent" and ".send \(", respectively, and the replacement shouldn't use quotes.

Any ideas?

[lnminente]

Not sure if you are looking for a filter or for a javascript. I know we can override/redefine functions, don't know how to do it, but maybe it would be the safest way...

How to redefine javascript native functions

[sidki3003]

(Jan. 03, 2009 05:58 PM)lnminente Wrote:  Not sure if you are looking for a filter or for a javascript.

Whatever works.


The thing with above two cases is that "userAgent" is a read-only (no override whatsoever) property of "Navigator" (which may come with a different object name), and that "send" is a method of the XMLHttpRequest object which is entirely different in IE6 and W3C browsers.

[lnminente]

This could help someone: http://www.w3schools.com/htmldom/dom_obj_navigator.asp