How to call loading function with React useEffect only once

👋 Hey tech-savvy folks! Are you struggling with making your React useEffect hook call a loading function only once? 🤔 Don't worry, I've got you covered! In this blog post, I'll walk you through a quick and easy solution to this common problem. 💪

Before we dive into the solution, let's briefly understand the context. The useEffect hook in React is designed to run the passed-in function on every change. However, sometimes we need to call an initialization function from componentDidMount and prevent it from being called again when there are subsequent changes. 👍

Consider the following class-based component code snippet:

class MyComponent extends React.PureComponent {
  componentDidMount() {
    loadDataOnlyOnce();
  }
  render() {
    // ...
  }
}

Now, in the hooks world, this can be achieved as follows:

import React, { useEffect } from 'react';

function MyComponent() {
  useEffect(() => {
    loadDataOnlyOnce(); // 🚀 But wait, this will fire on every change 😱
  }, [...???]);
  return (
    // ...
  );
}

Here's the million-dollar question: what should we put in those square brackets ([...???) to ensure that the loadDataOnlyOnce function is only called once, and not triggered unnecessarily? 🤔

The easy-peasy solution lies in providing an empty array as the second argument for the useEffect hook, like so:

import React, { useEffect } from 'react';

function MyComponent() {
  useEffect(() => {
    loadDataOnlyOnce(); // 🎉 Voila! This will now only fire once 🙌
  }, []);
  return (
    // ...
  );
}

By passing an empty array, we're essentially telling React that there are no dependencies for this useEffect hook. As a result, the hook will be triggered only once, mimicking the behavior of componentDidMount. 🚀

Time to put this solution into action and enjoy the benefits of loading your entity efficiently without any unnecessary function calls! 🎉

If you found this blog post helpful, be sure to share it with your fellow React enthusiasts. And don't forget to subscribe to my newsletter for more exciting tech tips and tricks! 💌

Now go ahead and implement this solution in your React projects. Happy coding! 💻🚀