const storage = {
	has(key) {
  	return !!localStorage.getItem(key);
  },
  get(key) {
  	return JSON.parse(localStorage.getItem(key));
  },
  set(key, value) {
  	localStorage.setItem(key, JSON.stringify(value));
  }
};

//Usage with jQuery 3.3.1 (onload)
(function(){
  storage.set('yourkey', 'CTH001239');
  if(storage.has('yourkey')){
    console.log(storage.get('yourkey'));
    console.log('Found!');
  } else {
  console.log('Not found!');
  }
})();