Question

I have got:

var myclass = 'moreElements showAddElements-570';
var re = new RegExp('showAddElements\-\d*');
var m = re.exec(myclass);

alert(m[0]);
alert(m[1]);

First alert results in ‘showAddElements-‘, second alert in ‘undefined’. I would like to get ‘570’, what I am doing wrong here? If I test it, I get there at least ‘showAddElements-570’ … what am I doing wrong here?

Thx for any tipps!

P.s.: I’d like the number only after ‘showAddElements-‘, all other numbers should be omitted..

Answer 1

Simply use the correct regex:

var re = /showAddElements-(\d+)/;

I removed the backslash before the dash (not needed) and added parens around the digits to turn it into a capturing group — otherwise m[1] would always be undefined.

See it in action.