How to call a js function on a remote host?

Question

how to write a program/script that will click a button on a web page? The button's function is:OnClick="func();". Firebug gives no information about the called function, so I can't call an AJAX query.

:)

Answer 1

There is click method for Input and Anchor element.

Answer 2

You can't do this with JavaScript, without dumping the contents of the page on your page or using an iframe. And, you can't interact with elements inside iframes from outside of it (unless it is on the same domain; thanks @Pekka)

Answer 3

You can't do that unless you control the server of web page to some extent (in which case you can use cross-domain AJAX or something equivalent), but you might be able to replicate the effect of clicking the button. This is known as a CSRF attack.

Answer 4

Let's say you have button A. When button A is pressed, function X is supposed to run. You could use the click method as DoubleThink suggested, or you could just directly run function X.

option 1 = document.getElementById('A').click()

option 2 = X()

Note: many people suggest doing this: document.getElementById('A').onclick(), but there are multiple ways to bind functions to events and this way does not cover all those ways -- it only covers the case where someone had <button onclick="..."/>. For Example, if you use jQuery, using .onclick will not suffice.