Has anyone got any experience with overriding the alert() function in JavaScript?   Which browsers support this? Which browser-versions support this? What are the dangers in overriding the function?...

Let's say you have the below code:  function A() {     function modify() {        x = 300;        y = 400;     }      var c = new C(); }  function B() {     function modify(){        x = 3000;        y = 4000;     }      var c = new C(); }  C = f...

How would I be able to override the XMLHttpRequest.open() method and then catch and alter it's arguments?  I've already tried the proxy method but it didn't work, although removing the open over-rid when XMLHttpRequest() was called:   (fu...

For example:  (function() {       var proxied = window.eval;       window.eval = function() {         return proxied.apply(this, arguments);       };     })();   But this code is not working....

If a javascript function is declared anonymously is there any way to override it or portions of it?  I am attempting to stop google.com's instant search from hijacking the up and down arrow keys to move through your search rankings. I have identi...

Lets say we have alert method of window object. I would like to enhance it with nice alertbox.  Also I want to save the existing alert method so that we can switch back once our application is over.  Something like this, but its throwing error in fir...

I have a JavaScript file, Mybasefile.js, which has the function Mybasefunction(). I want to override this function in another JavaScript file. When the function is called in a button click, I want the original Mybasefunction() to be executed along wi...

function Ninja(){   this.swingSword = function(){     return true;   }; }  // Should return false, but will be overridden Ninja.prototype.swingSword = function(){   return false; };  var ninja = new Ninja(); log( ninja.swingSword(), "Calling the...

I have a custom Javascript class (created using John Resig's Simple Javascript Inheritance). I want to be able to compare two instances of this class, using the ==, <, >, >=, and <= symbols.  How do I override the comparators of my cu...

Are there ways where I can use jQuery to improve the performance of a file uploader? There's a system where I am trying to hack to make the uploading process better. I am just doing some frontend override as I don't have permission to their s...