Increment a number in a string in with regex

Question

I get the name of an input element, which is a string with a number (url1). I want to increment the number by 1 (url2

Answer 1

Simple. Use a substitution function with regular expressions:

s = 'abc99abc';
s = s.replace(/\d+/, function(val) { return parseInt(val)+1; });

will set variable s to: abc100abc

But it gets more complicated if you want to make sure you only change a certain parameter in the URL:

s = '?foo=10&bar=99';
s = s.replace(/[&?]bar=\d+/, function(attr) {
  return attr.replace(/\d+/, function(val) { return parseInt(val)+1; });
});

will set variable s to: ?foo=10&bar=100