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JavaScript React by Example Refining the App Filter Bug: Solution

2 Answers

I would recommend treehouse Using Local Storage with JavaScript tutorial, a nice kit to have in your arsenal.

Bobby Verlaan
Bobby Verlaan
29,370 Points

Here some code that needs to go in the App component (in App.js) that will save your state in localStorage

  componentWillMount() {
    // Retrieve state from local storage
    const data = localStorage.getItem("state");

    // Parse JSON to JavaScript object
    const state = JSON.parse(data);

    // Set state to the retrieved JavaScript object
    this.setState(state);
  }

  componentDidMount() {
    // Add event listener that will execute code before page refresh
    window.addEventListener("beforeunload", () => {
      // Stringify the state object, so it can be saved as a text value
      const data = JSON.stringify(this.state);

      // Set localStorage item
      localStorage.setItem("state", data);
    });
  }

Make sure you change your newGuestId method and work with state too, so you keep incrementing your GuestId count after page refresh :-)