JSFiddle - React, Tailwind, and code Playground
JavaScript
var target = [];
target["1"] = "Films-by-Name-C7";
alert((target[1].lastIndexOf('?') > 0 ?target[1].slice(0, target[1].indexOf("?")).substr((target[1].lastIndexOf('C')+1)):target[1].substr(-(target[1].length-target[1].lastIndexOf('C')-1))));