ReactJS Components and Elements

Elements and components are the fundamental components of the programs you develop using ReactJS. These are, naturally, the most essential concepts you must master before starting with React. Although they are both structural or functional pieces of your code, elements and components behave very differently from one another. From a React software development company, let’s look at how.

ReactJS is currently one of the most popular libraries used among developers to build adaptable, dynamic UIs for apps today. The JavaScript library that is hosted by Facebook distinguishes itself from rival frameworks thanks to a number of distinctive features. Although the ReactJS technology is dedicated to making the creation of apps easier for us, it also ensures that the finished products made with it function at their best. Because of capabilities like virtual DOM, applications created with ReactJS are quite immersive. Other properties, like as reusable components, make it simpler for us to create apps. We can always use our creativity to develop React apps given the resources and time reductions. If you are unfamiliar with React or have decided to learn it due to these features, you are likely to comprehend the core concepts of ReactJS. ReactJS’s elements and components are the first of these ideas.

Are Elements and Components the same things in ReactJS?

No, not at all. The idea of components may be said to be the most important ReactJS topic to know or learn. In this method, the components of JavaScript and React might be compared. The basic parts of your code in ReactJS are called elements, and your user interface is pieced together using components. Components generate element trees as returns using props as input. They come together to create the main framework for your ReactJS-based UI. The concept of elements and components is among the initial topics you encounter when mastering ReactJS or JavaScript as a result. Because they are both important components of your code, you would instantly consider the two as somehow being relatively comparable. Both data input and output activities are sent to the UI by them. They are actually two quite different groups of ReactJS components, as can be seen with just a little more in-depth investigation.

The smallest components of React apps are referred to as elements, as simply as possible. React uses straightforward Javascript objects—not to be confused with browser DOM elements—as its building blocks.

Elements

Objects are a JavaScript notion. Objects are simply entities with specific sorts and properties, to put it simply. Similar to how pens come in many colors, shapes, and variations like ballpoint pens and brush pens, JS objects also have attributes that are attributed to them and define their personalities. The appearance of a welcome screen, the date, and other things are instances of objects in JS. Everything in Javascript, excluding primitives (such as the value of pi), is an object. They frequently combine variables, functions, and data structures. A collection of name assortment of factors up an object. They become a compilation and help our codes to be simpler to read.

Creating an Element in ReactJS

Declaring what we want to appear on the screen is the best method to explain constructing an element in React Elements. React virtual DOMs handle real DOMs to meet React elements. Elements combine to form components. We’ll talk about it in the section that follows this. Let’s examine a React element creation example.

The element below was created using React.createElement(). It is a function that incorporates the element’s type, attributes, and offspring into account. In this instance, we created an element with null-valued h1 parameters. The phrase “Hello Reader” is supplied in the form of its children.

import React from ‘react’;

import React from ‘react’;

import ReactDOM from ‘react-dom’;

// Without JSX

const ele1 = React.createElement(

‘h1’,

{id:’header’},

‘Hello Learner’

);

ReactDOM.render(ele1,document.getElementById(‘root’));

The following object would returned from the above:

{

type: ‘h1’,

props: {

children: ‘Hello Learner’,

id: ‘header’

}

}

Updating Elements in ReactJS

React elements are not able to have their children or attributes changed after they have been constructed. Let’s consider the following analogy. An element is something like a single image in a clip. The clip can be altered by adding, removing, or swapping frames. Elements can only be updated by being replaced with new ones. This is accomplished by passing the element through the root.render(). Because its components are both inexpensive to build and simple to employ, ReactJS makes this reasonably easy. The virtual DOM, as I mentioned before, analyses an element’s children and attributes and therefore only modifies the DOM as needed to bring it to the appropriate state. This lessens bugs because the full UI doesn’t have to be refreshed. In principle, modifying a component only calls for changing one component-wide element or line of code.

Let’s have a look at an example of an element that displays the time. For it to work effectively, this component must be modified every second. How is this possible if elements cannot be changed? In the example below, the element is updated because a setInterval() callback contacts the root.render() once every second.

const root = ReactDOM.createRoot(

document.getElementById(‘root’)

);

function tick() {

const element = (

<div>

<h1>Hello Learner </h1>

<h2>It is {new Date().toLocaleTimeString()}.</h2>

</div>

);

root.render(element);

}

setInterval(tick, 1000);

Components

Components make up the user interface (UI) of React apps. They act as the UI’s building blocks or models. The user interface can be divided into components thanks to ReactJS, to put it another way. This allows for distinct control of various UI elements. Components serve as individual, reusable parts.

In a sense, components represent functions in Javascript. They return elements in react, which take arbitrary inputs called props, to describe what should be displayed on the screen. Class components along with function components are two of the distinct types of components in ReactJS.

Creating Function Components in ReactJS

Simple js functions are used to create function parts. They accept data-only parameters for single props and generate a react element’s output. Prop is the short form of properties. Let’s examine a function component demonstration using a passing user as that of the prop.

import React from ‘react’;

import ReactDOM from ‘react-dom’;

function Welcome(user){

return <div>

<h3> Hello {user.name}</h3>

</div>

}

const ele = <Welcome name=”Learner”/>

ReactDOM.render(ele,document.getElementById(“root”));

Creating a Class Component in ReactJS

A component is declared in the class components using the ES6 class. Smaller components may be composed of larger components, while larger components may be broken into smaller components. Because of this, it is simpler to extract and reuse component pieces than it could otherwise be. This can be due to the fact that complex components usually have a lot of nesting. Props are non-changeable. Functions can be classified as either pure or impure. In pure functions, props are fixed; in impure functions, they are variable. There is a strict restriction in React that all components must handle props as if they were pure functions. Dynamic props can be updated using state. Components may change their props and save variables in a specific source thanks to the state.

Here is a simplistic ticking-clock class component code that uses state variables:

class App extends React.Component {

state = {

date: “”

};

getDate() {

var date = { currentTime: new Date().toLocaleString() };

this.setState({

date: date

});

}

render() {

return (

<div class=”date”>

<p> ddd {this.state.date}</p>

</div>

);

}

}

export default App;

The Key Differences in ReactJS between an Element vs a Component

We now have a strong understanding of the completely diverse characteristics and applications of ReactJS’s components and elements. React’s user interfaces are built through components, which are built through elements.

Let’s quickly go through the key differences between React components and elements.

Summary

The discussion of the differences across elements and components in ReactJS is now complete. Even though both act as building blocks, elements and components have different hierarchies. The user interfaces in React apps are composed of components that are derived from elements. As a consequence, there are some obvious differences in how pieces and components are made and what materials they are made of. We have condensed them in the table to make them simpler to understand. The primary building block for constructing ReactJS applications is understanding how to build elements and components. I believe I was able to clear up any misunderstanding you could have had on the distinctions between the two.

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