How to store an array of objects in Local Storage?

Question

This is my code. I am trying since a couple of days to create an Array of Objects, which I will then store in Local Storage. Here is the problem, I need to first Get the existing value from Local Storage. I then need to add the new data object to the existing array. I then convert it into JSON so that I can store it back in the local storage. ``` onRegisterSubmit(){ const user = { a: this.a, b: this.b, c: this.c, id: Date.now() } var abc = []; var get = JSON.parse(localStorage.getItem('user')); abc = [get]; abc.push(user); localStorage.setItem('user', JSON.stringify(abc)); console.log(JSON.stringify(abc)); console.log(get); } ``` I want the JSON to be an array of objects like this, ``` [{"hour":1,"minute":21,"ampm":"PM","repeatDays":[],"message":"","todayOrTomorrow":"Tomorrow","isRepeatMode":false,"isEnabled":false,"id":"1493797882440"},{"hour":1,"minute":24,"ampm":"PM","repeatDays":[],"message":"","todayOrTomorrow":"Tomorrow","isRepeatMode":false,"isEnabled":false,"id":"1493797896257…

Accepted Answer

The issues with that code are:

You're wrapping the result you get in an array, but in theory, you want to already have an array.

You're storing `user`, not `get` or `abc`. (You removed that with an edit.)

To store the array, do what you're doing:

```
localStorage.setItem("users", JSON.stringify(users));
```

To get the array:

```
users = JSON.parse(localStorage.getItem("users") || "[]");
```

Note how that provides a default (empty array) if `getItem` returns `null` because we've never stored our users there.

To add a user to the array:

```
users.push({id: 1, foo: "bar"});
```

Example (live on jsFiddle [Stack Snippets don't allow local storage]):

```
(function() { // Scoping function to avoid creating globals
    // Loading
    var users = JSON.parse(localStorage.getItem("users") || "[]");
    console.log("# of users: " + users.length);
    users.forEach(function(user, index) {
        console.log("[" + index + "]: " + user.id);
    });

// Modifying
    var user = {
        id: Math.floor(Math.random() * 1000000)
    };
    users.push(user);
    console.log("Added user #" + user.id);

// Saving
    localStorage.setItem("users", JSON.stringify(users));
})();
```

That shows you the list of current users in the console, adding one each time you refresh the page.

How to store an array of objects in Local Storage?

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