Insert a string before the extension in a filename

Question

How can I insert a string before the extension in an image filename? For example, I need to convert this:

../Course/Assess/Responsive_Course_1_1.png

Answer 1

var s = '../Course/Assess/Responsive_Course_1_1.png'
s.replace(/\.png$/, '_large.png');

This will do the job. By the way, it's night here. :)

UPDATE:

A more general way would be this:

var s = '../Course/Assess/Responsive_Course_1_1.png';
s.replace(/(\.[^\.]+)$/, '_large$1');