kontra/src/store.js

Kontra HTML5 game development library

/**
 * A simple interface to LocalStorage based on [store.js](https://github.com/marcuswestin/store.js), whose sole purpose is to ensure that any keys you save to LocalStorage come out the same type as when they went in.
 *
 * Normally when you save something to LocalStorage, it converts it into a string. So if you were to save a number, it would be saved as `"12"` instead of `12`. This means when you retrieved the number, it would now be a string.
 *
 * ```js
 * import { setStoreItem, getStoreItem } from 'kontra';
 *
 * setStoreItem('highScore', 100);
 * getStoreItem('highScore');  //=> 100
 * ```
 * @sectionName Store
 */

/**
 * Save an item to localStorage.
 * @function setStoreItem
 *
 * @param {String} key - The name of the key.
 * @param {*} value - The value to store.
 */
export function setStoreItem(key, value) {
  if (value === undefined) {
    localStorage.removeItem(key);
  }
  else {
    localStorage.setItem(key, JSON.stringify(value));
  }
}

/**
 * Retrieve an item from localStorage and convert it back to its original type.
 * @function getStoreItem
 *
 * @param {String} key - Name of the key of the item to retrieve.
 *
 * @returns {*} The retrieved item.
 */
export function getStoreItem(key) {
  let value = localStorage.getItem(key);

  try {
    value = JSON.parse(value);
  }
  catch(e) {}

  return value;
}