Skip links

Essential Javascript for React That Every Developer Should Know

Jump To Section

You don’t need to be a JavaScript expert to start your ReactJS journey, but just as knowledge of ingredients is a must for any chef hoping to master cooking, the same is true for learning ReactJS. It’s a modern JavaScript UI library, so you need to know some JavaScript.

You don’t need to be a JavaScript expert to start your ReactJS journey, but just as knowledge of ingredients is a must for any chef hoping to master cooking, the same is true for learning ReactJS. It’s a modern JavaScript UI library, so you need to know some essential JavaScript for react.

Necessary JavaScript Concepts For React:

  • Functions and Arrow Functions.
  • Objects.
  • Arrays and array methods.
  • Destructuring.
  • Template literals.
  • Ternary Operators.
  • ES Modules and Import/Export Syntax.

Functions and Arrow Functions:

In JavaScript, there are two types of functions. You have normal functions and arrow functions.Let’s explore the difference between them.

Arrow functions was introduced in ES6. And it introduced a simple and shorter way to create functions.Here’s how to create a normal function, with arguments, which returns something:

function multiply(num1, num2) {
const result = num1 * num2
return result
}

If want to transform this into an arrow function:

const multiply = (num1, num2) => {
const result = num1 * num2
return result
}

If the return statement is the only statement in the function, you can even have a shorter function expression. For example:

const multiply = (num1, num2) => {
return num1 * num2
}

This function only contains the return statement. With arrow functions, we can have something shorter like this:

const multiply = (num1, num2) => num1 * num2

We skip the curly braces and the return keyword. Shorter; one-liner.

JavaScript Objects:

In JavaScript, an object is an unordered collection of key-value pairs. Each key-value pair is called a property.

The key of a property can be a string. And the value of a property can be any value, e.g., a string, a number, an array, and even a function.

JavaScript provides you with many ways to create an object. The most commonly used one is to use the object literal notation.

The following example creates an empty object using the object literal notation:

let empty = {};

To create an object with properties, you use the key:value within the curly braces. For example, the following creates a new person object:

let person = {
firstName: 'John',
lastName: 'Doe'
};

The person object has two properties firstName and lastName with the corresponding values ‘John’ and ‘Doe’. When an object has multiple properties, you use a comma (,) to separate them like the above example.

JavaScript Arrays and Array Methods:

An array is a special variable, which can hold more than one value.

const cars = [“Volvo”, “BMW”, “Honda”];

You can able to create an array using an array literal.

const array_name = [item1, item2, . . .];

You can also create an array using the JavaScript keyword new

const cars = new Array(“Volvo”, “BMW”, “Honda”);

An array is a data structure that contains list of elements which store multiple values in a single variable. The strength of JavaScript arrays lies in the array methods. Array methods are functions built-in to JavaScript that we can apply to our arrays – Each method has a unique function that performs a change or calculation to our array and saves us from writing common functions from scratch.

Essential Javascript Array

Destructuring:

The destructuring assignment syntax is a JavaScript expression that makes it possible to unpack values from arrays, or properties from objects, into distinct variables. Example for simple Destructuring,

const vehicles = ['mustang', 'f-150', 'expedition'];
const car = vehicles[0];
const truck = vehicles[1];
const suv = vehicles[2];

Template Literals:

Template literals are literals delimited with backtick ( ` ) characters, allowing for multi-line strings, string interpolation with embedded expressions, and special constructs called tagged templates.

const name = 'Jack';
console.log(`Hello ${name}!`); // Hello Jack!

Ternary Operators:

The conditional (ternary) operator is the only JavaScript operator that takes three operands: a condition followed by a question mark ( ? ), then an expression to execute if the condition is truthy followed by a colon ( : ), and finally the expression to execute if the condition is false.

The ternary operator can be a good replacement for if statements in some cases. It allows you to write concise, cleaner, and easier-to-read lines of code if used well.

let age = 18;
let message;

if (age >= 16) {
message = 'You can drive.';
} else {
message = 'You cannot drive.';
}

console.log(message);
let age = 18;
let message;

message = age >= 16 ? 'You can drive.' : 'You cannot drive.';

console.log(message);

ES Modules and Import/Export Syntax:

With ES2015 (ES6), with get built-in support for modules in JavaScript. Like with CommonJS, each file is its own module. To make objects, functions, classes or variables available to the outside world it’s as simple as exporting them and then importing them where needed in other files.

Exporting:

You can export members one by one. What’s not exported won’t be available directly outside the module.

export const myNumbers = [1, 2, 3, 4];
const animals = ['Panda', 'Bear', 'Eagle']; // Not available directly outside the module

export function myLogger() {
console.log(myNumbers, animals);
}

export class Alligator {
constructor() {
// ...
}
}

Importing:

Importing is also very straightforward, with the import keyword, members to be imported in curly brackets and then the location of the module relative to the current file.

import { myLogger, Alligator } from 'app.js';

So far all the important concepts are covered and these are the necessary JavaScript things to learn react.

Jagadeesh Ruthrakotti

Jagadeesh Ruthrakotti

Latest Reads

Subscribe

Suggested Reading

Ready to Unlock Yours Enterprise's Full Potential?

Adaptive Clinical Trial Designs: Modify trials based on interim results for faster identification of effective drugs.Identify effective drugs faster with data analytics and machine learning algorithms to analyze interim trial results and modify.
Real-World Evidence (RWE) Integration: Supplement trial data with real-world insights for drug effectiveness and safety.Supplement trial data with real-world insights for drug effectiveness and safety.
Biomarker Identification and Validation: Validate biomarkers predicting treatment response for targeted therapies.Utilize bioinformatics and computational biology to validate biomarkers predicting treatment response for targeted therapies.
Collaborative Clinical Research Networks: Establish networks for better patient recruitment and data sharing.Leverage cloud-based platforms and collaborative software to establish networks for better patient recruitment and data sharing.
Master Protocols and Basket Trials: Evaluate multiple drugs in one trial for efficient drug development.Implement electronic data capture systems and digital platforms to efficiently manage and evaluate multiple drugs or drug combinations within a single trial, enabling more streamlined drug development
Remote and Decentralized Trials: Embrace virtual trials for broader patient participation.Embrace telemedicine, virtual monitoring, and digital health tools to conduct remote and decentralized trials, allowing patients to participate from home and reducing the need for frequent in-person visits
Patient-Centric Trials: Design trials with patient needs in mind for better recruitment and retention.Develop patient-centric mobile apps and web portals that provide trial information, virtual support groups, and patient-reported outcome tracking to enhance patient engagement, recruitment, and retention
Regulatory Engagement and Expedited Review Pathways: Engage regulators early for faster approvals.Utilize digital communication tools to engage regulatory agencies early in the drug development process, enabling faster feedback and exploration of expedited review pathways for accelerated approvals
Companion Diagnostics Development: Develop diagnostics for targeted recruitment and personalized treatment.Implement bioinformatics and genomics technologies to develop companion diagnostics that can identify patient subpopulations likely to benefit from the drug, aiding in targeted recruitment and personalized treatment
Data Standardization and Interoperability: Ensure seamless data exchange among research sites.Utilize interoperable electronic health record systems and health data standards to ensure seamless data exchange among different research sites, promoting efficient data aggregation and analysis
Use of AI and Predictive Analytics: Apply AI for drug candidate identification and data analysis.Leverage AI algorithms and predictive analytics to analyze large datasets, identify potential drug candidates, optimize trial designs, and predict treatment outcomes, accelerating the drug development process
R&D Investments: Improve the drug or expand indicationsUtilize computational modelling and simulation techniques to accelerate drug discovery and optimize drug development processes