I have a string:
var example = 'sorted-by-' + number;
Where number variable can be any positive integer. I don't know how to reverse this process, not knowing how many digits this number has. I want to get from example string a number at the end.
var outputNumber = example.substring(10);
This is the simple solution because example string always start with 'sorted-by-'.
let num = + string.substr(10);
You can use String#replace function to replace sorted-by- to empty string and after that convert left part to a number:
var example = 'sorted-by-' + 125;
var num = +example.replace('sorted-by-', '');
console.log(num);You can split string at - and get last element using pop().
var example = 'sorted-by-' + 100.99
var n = +(example.split('-').pop())
console.log(n)You can also use regex for this.
var number = 245246245;
var example = 'sorted-by-' + number;
var res = example.match(/^sorted-by-(\d+)/);
console.log(+res[1]);