Question

Using javascript — I need to pull out and examine the number that appears just before the “jpg” file extension, in this case “300”.

var filename = 2012_honda_odyssey_passenger-minivan_ex_s_oem_2_300.jpg

What’s the best way to pull this number out — I can alway assume it will be between the last “_” in the string and this final “.” before the file extension.

I’m guessing that I need to do something with regex. Like this ….

var num = parseInt(filename.match(/some-regex-here/), 10);

addition

I did come up with this … but it seemed very kludgy.

var filename = "2012_honda_odyssey_passenger-minivan_ex_s_oem_2_300.jpg";
var num = parseInt(filename.split('_').splice(-1,1).toString().split(".").splice(0,1).toString(), 10);

Answer 1

I feel a regex is overkill for something this simple, I would just use this:

var start = filename.lastIndexOf('_') + 1; 
var end = filename.lastIndexOf('.');
var num = parseInt(filename.substring(start, end), 10);