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ReactJS How to pass object in html element attribute

Understanding the Challenge

Let's start by setting the stage. You're working on a ReactJS project, and you find yourself needing to pass an object as an attribute to an HTML element. But wait, HTML elements don't normally accept objects as attributes. They usually take in strings. So how do you get around this?

That's the challenge we're going to tackle today. But before we move forward, let's quickly explain what we mean by "objects" and "attributes".

In programming, an object is a collection of related data and/or functionality, which can include multiple variables and functions. In JavaScript, an object could look like this:

var student = {
  firstName: "John",
  lastName: "Doe",
  age: 20,
  getFullName: function() {
    return this.firstName + " " + this.lastName;

An attribute, on the other hand, is a modifier of an HTML element. It provides additional information about the element, such as its id, class, style, etc. For instance, in the following HTML line, "src" and "alt" are attributes:

<img src="image.jpg" alt="A beautiful sunset">

The Data Attribute: Our Lifesaver

Luckily for us, HTML5 introduced a feature that can help us: the data attribute. You can use data attributes to store extra information on standard, semantic HTML elements without other hacks such as non-standard attributes, extra properties on DOM, or Node.setUserData().

Data attributes are named starting with the word "data-", followed by anything you want, as long as it doesn't contain capital letters. For instance, if you wanted to store a person's age on a div, you could do something like this:

<div data-age="30">Hello World</div>

But our challenge is a bit more complex. We want to store an entire object, not just a single value.

Turning Objects into Strings: JSON.stringify()

Here comes a handy tool provided by JavaScript: JSON.stringify(). This method converts a JavaScript object into a string. It's perfect for our case, because, as we said before, HTML elements can only take strings as attributes. Here's an example:

var student = {
  firstName: "John",
  lastName: "Doe",
  age: 20

If you run this code, you'll see a string representation of the student object in the console:


Let's Bring It All Together

Now that we have all the pieces of the puzzle, let's see how they fit together. We can start by creating our object and turning it into a string. After that, we can assign this string to a data attribute in our HTML element:

var student = {
  firstName: "John",
  lastName: "Doe",
  age: 20
var studentString = JSON.stringify(student);
document.querySelector('div').setAttribute('data-student', studentString);

And voilà! If you inspect the div in your browser's developer tools, you'll see the data attribute with the stringified object:

<div data-student="{\"firstName\":\"John\",\"lastName\":\"Doe\",\"age\":20}">Hello World</div>

Retrieving the Object: JSON.parse()

But what if you want to get your object back? You can use another JavaScript method: JSON.parse(). This method turns a string into a JavaScript object. Here's how you can retrieve your student object from the div:

var studentString = document.querySelector('div').getAttribute('data-student');
var student = JSON.parse(studentString);

If you run this code, you'll see the student object in your console:

{firstName: "John", lastName: "Doe", age: 20}


Just like a magician pulling a rabbit out of a hat, we managed to sneak an object into an HTML attribute. And not just that, we also brought it back to its original form. We overcame HTML's limitation by using two powerful JavaScript tools: JSON.stringify() and JSON.parse().

But remember, with great power comes great responsibility. It's not always a good idea to store complex data in HTML attributes. It can make your code harder to understand and maintain. However, knowing how to do it can be handy in certain situations.

So next time you're faced with a similar challenge, you'll know what to do. You'll be like a programming Houdini, pulling off tricks that seem impossible at first glance. But unlike Houdini, you'll always share your secrets with your fellow programmers. Because that's how we all get better, by learning from each other. And that's the real magic of programming.