React-session-hooks NPM

react-session-hooks

A lightweight React library providing custom hooks for managing state synchronized with localStorage and sessionStorage that works with Server Side Rendering frameworks.

Installation

To install the library, use npm or yarn:

npm install react-session-hooks

yarn add react-session-hooks

Ensure you also have React as a peer dependency:

npm install react

Usage

useLocalState

The useLocalState hook allows you to manage state that persists across page reloads using localStorage.

It includes a listener to maintain synchronization.
It will return null if there is any error in serializing or deserializing data.
It will remove the item from storage if the value is set to undefined, null, or "".

import { useLocalState } from "react-session-hooks";

const MyComponent = () => {
  const [value, setValue, loading] = useLocalState("myKey", "default");

  if (loading) return <div>Loading...</div>;

  return (
    <div>
      <p>Current value: {value}</p>
      <button onClick={() => setValue("newValue")}>Update Value</button>
    </div>
  );
};

useSessionState

The useSessionState hook allows you to manage state that persists only within the current browser session using sessionStorage.

It includes a listener to maintain synchronization.
It will return null if there is any error in serializing or deserializing data.
It will remove the item from storage if the value is set to undefined, null, or "".

import { useSessionState } from "react-session-hooks";

const MyComponent = () => {
  const [value, setValue, loading] = useSessionState("myKey", "default");

  if (loading) return <div>Loading...</div>;

  return (
    <div>
      <p>Current value: {value}</p>
      <button onClick={() => setValue("newValue")}>Update Value</button>
    </div>
  );
};

API

useLocalState API

const [storedValue, setStoredValue, loading] = useLocalState<T>(
  key: string,
  defaultValue?: T,
  serialize?: (value: T) => string,
  deserialize?: (value: string) => T
);

Parameters

key (string): The key under which the value is stored in localStorage.
defaultValue (T, optional): The default value to use if no value is found in localStorage.
serialize ((value: T) => string, optional): Custom serialization function.
deserialize ((value: string) => T, optional): Custom deserialization function.

Returns

storedValue: The current value stored in localStorage.
setStoredValue: A function to update the stored value.
loading: A boolean indicating whether the hook is currently loading the initial value.

useSessionState API

const [storedValue, setStoredValue, loading] = useSessionState<T>(
  key: string,
  defaultValue?: T,
  serialize?: (value: T) => string,
  deserialize?: (value: string) => T
);

Parameters

key (string): The key under which the value is stored in sessionStorage.
defaultValue (T, optional): The default value to use if no value is found in sessionStorage.
serialize ((value: T) => string, optional): Custom serialization function.
deserialize ((value: string) => T, optional): Custom deserialization function.

Returns

storedValue: The current value stored in sessionStorage.
setStoredValue: A function to update the stored value.
loading: A boolean indicating whether the hook is currently loading the initial value.

Example Scenarios

useLocalState example

Here’s a simple example of using useLocalState to manage a user’s preferred language setting:

import { useLocalState } from "react-session-hooks;

const LanguageSelector = () => {
  const [language, setLanguage, loading] = useLocalState(
    "preferredLanguage",
    "English"
  );

  if (loading) return <div>Loading...</div>;

  return (
    <div>
      <p>Selected language: {language}</p>
      <button onClick={() => setLanguage("English")}>English</button>
      <button onClick={() => setLanguage("Spanish")}>Spanish</button>
    </div>
  );
};

useSessionState Example

As shown previously, useSessionState can be used in a form to manage user input within a session:

import { useSessionState } from "your-library-name";

const MyForm = () => {
  const [formValue, setFormValue, loading] = useSessionState("formData", "");

  if (loading) return <div>Loading...</div>;

  const handleChange = (event) => {
    setFormValue(event.target.value);
  };

  return (
    <form>
      <input type="text" value={formValue} onChange={handleChange} />
      <button type="submit">Submit</button>
    </form>
  );
};