Detecting localStorage Changes on the Same Page

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window.addEventListener("storage", () => {});

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// Save original methods
Storage.prototype._setItem = Storage.prototype.setItem;
Storage.prototype._getItem = Storage.prototype.getItem;
Storage.prototype._removeItem = Storage.prototype.removeItem;
Storage.prototype._clear = Storage.prototype.clear;

// Override setItem
Storage.prototype.setItem = function (key, value) {
  const oldValue = this._getItem(key);
  this._setItem(key, value);

  const evt = new CustomEvent("storagechange", {
    detail: {
      type: "set",
      key: key,
      newValue: value,
      oldValue: oldValue,
    },
  });
  window.dispatchEvent(evt);
};

// Override getItem
Storage.prototype.getItem = function (key) {
  const value = this._getItem(key);

  const evt = new CustomEvent("storagechange", {
    detail: {
      type: "get",
      key: key,
      value: value,
    },
  });
  window.dispatchEvent(evt);

  return value;
};

// Override removeItem
Storage.prototype.removeItem = function (key) {
  const oldValue = this._getItem(key);
  this._removeItem(key);

  const evt = new CustomEvent("storagechange", {
    detail: {
      type: "remove",
      key: key,
      oldValue: oldValue,
    },
  });
  window.dispatchEvent(evt);
};

// Override clear
Storage.prototype.clear = function () {
  this._clear();

  const evt = new CustomEvent("storagechange", {
    detail: {
      type: "clear",
    },
  });
  window.dispatchEvent(evt);
};

// Listen for events
window.addEventListener("storagechange", (e) => {
  console.log("LocalStorage changed:", e.detail);
});