LocalStorage with basic types & JSON support

gistfile1.txt

const setItem = (key: string, value: any) => {
  const payload: any = {};

  if (!value) {
    payload.nullValue = true;
  } else if (typeof value === 'number') {
    payload.numberValue = Number(value);
  } else if (typeof value === 'string') {
    payload.stringValue = String(value);
  } else {
    payload.value = value;
  }

  localStorage.setItem(key, JSON.stringify(payload));
};

const getItem = (key: string) => {
  const raw = localStorage.getItem(key);
  try {
    const { nullValue, numberValue, stringValue, value } = JSON.parse(raw);

    if (nullValue) {
      return null;
    }

    if (numberValue !== undefined) {
      return numberValue;
    }

    if (stringValue !== undefined) {
      return stringValue
    }

    return value;
  } catch {
    return raw;
  }
};