javascript regex question ?

Question

I have following div:

<div id = "zone-2fPromotion-2f" class = "promotion">

How can I get value 2f present in the end, actually it is the value of Promotion and how can I retrieve it ?

I was using

this.match = this.id.match(/(Promotion)-([0-9a-f]{2})/);

but it is not giving me exact result but it gives me array of (Promotion-2f, Promotion, 2f) but this is not what I require. Any guidance and also if any one can refer me to good online resource for regex, it would highly helpful and appreciated.

Answer 1

that's what you want. the results of the match are firstly the entire matched part of the expression, and then the various groups. so since you want to retrieve group 2 (the second lot of ()'s ) just do

this.match = this.id.match(/(Promotion)-([0-9a-f]{2})/)[2];

also, the best online reference i've found is http://www.regular-expressions.info/

edit: you could just leave out the ()'s around Promotion, since you're not worried about returning that part, and do this

this.match = this.id.match(/Promotion-([0-9a-f]{2})/)[1];

Answer 2

This is a good resource on regular expressions for all languages.

http://www.regular-expressions.info/javascript.html