I'm using CodePen for a ReactJS project.
I need to set the `localStorage` for a part of the state that is:

```js
this.state={
    Things:{
        element:"value",
        element2: "value"
    },
    activated:-1
}

```

Since I need to set only `Things` I decided to set the `localStorage` in the component lifecycle: `componentDidUpdate()`

```js
componentDidUpdate(prevProps,prevState){
    localStorage.setItem("myThings",JSON.stringify(this.state.Things));
}

```

Here if I call `console.log(localStorage.getItem("myThings"))` I don't get any stored value.

For the `localStorage` checking part I implemented a solution in the constructor because I read in the React documentation that one should prefer the constructor to the `componentWillMount()` method (although I tried the latter too).

```js
constructor(props){
    super(props);
    if (localStorage.getItem("myThings")!==null){
        this.state={
            Things:JSON.parse(localStorage.getItem("myThings")),
            activated:-1
        }
     }
     ...

```