JavaScript negative lookbehind issue

Question

I\'ve got some JavaScript that looks for Amazon ASINs within an Amazon link, for example

http://www.amazon.com/dp         


        

Answer 1

You need to use a lookahead to filter the /e/* ones out. Then trim the leading /e/ from each of the matches.

var source; // the source you're matching against the RegExp
var matches = source.match(/(?!\/e)..\/[A-Z0-9]{10}/g) || [];
var ids = matches.map(function (match) {
  return match.substr(3);
});