How to find whether a particular string has unicode characters (esp. Double Byte characters)

Question

To be more precise, I need to know whether (and if possible, how) I can find whether a given string has double byte characters or not. Basically, I need to open a pop-up to

Answer 1

Why not let the window resize itself based on the runtime height/width?

Run something like this in your pop-up:

window.resizeTo(document.body.clientWidth, document.body.clientHeight);