As the most popular frontend library, everyone wants to learn React.
ReactJS is fundamentally JavaScript.
But that doesn’t mean you must learn everything in JavaScript to move to ReactJS.
Let’s outline essential concepts you should know about JavaScript before moving to ReactJS.
Arrow Functions
Arrow functions are widely used in React.
The arrow function looks shorter and cleaner than the regular function.
Usually, the React components have the following structure:
Arrow functions do not have names.
If you wish to name it, assign it to a variable.
The difference between a regular and an arrow function is more than just the syntax.
Learn more about arrow functions inMozilladevelopers' documentation.
Destructuring
Destructuring is used to obtain data from complex data structures.
In JavaScript, arrays and objects can store many values.
you might manipulate the values and use them in different parts of the system.
To get these values, you have to destructure the variable.
notation or the bracket notation.
In ReactJS, you will use the destructuring concept to obtain and share values in your system.
Destructuring helps to avoid repetition and makes your code more readable.
Array Methods
You’ll encounter arrays several times while working on React projects.
An array is a collection of data.
You store data in arrays, so you’ve got the option to reuse them when needed.
Array methods are primarily used to manipulate, retrieve, and display data.
Some commonly used array methods aremap(),filter(), andreduce().
You must be familiar with thearray methodsto understand when to apply each.
For example, themap()method iterates over all the items in an array.
It acts on each element of the array to create a new array.
You will use array methods a lot in ReactJS.
Short Conditionals
Conditionals are statements that JavaScript uses to make decisions in code.
Short conditionals include && (and), II (or), and the Ternary Operator.
These are shorter expressions of conditions and the if/else statements.
The following example shows how to use a ternary operator.
These are widely used in React.
Template literals allow you to manipulate string data making them more dynamic.
Tagged template literals allow you to perform operations within a string.
These are shorter expressions of conditions and the if/else statements.
For example:
6.
Spread Operators
The Spread operator (…) copies the values of an object or array into another.
Its syntax consists of three dots followed by the name of the variable.
For example (…name).
It merges the properties of two arrays or objects.
The following example shows how to use the spread operator to copy the values of one variable to another.
you’re able to use the spread operator to do a number of operations.
You may use the spread operator in ReactJS to handle the state changes in components.
Why Learn ReactJS?
ReactJS is popular for good reason.
It has a short learning curve, reliable, and renders quickly to the DOM.
It supports standalone components and has great debugging tools.
ReactJS incorporates new JavaScript concepts from ECMAScript 6 (ES6).
Learning fundamental concepts in JavaScript will make it easier to develop projects in ReactJS.
To top it all, ReactJS has a great community that is constantly releasing new updates.
If you want to learn a JavaScript library, ReactJS would be a great pick.
The Next.js framework complements the limitations of ReactJS.
A combination of the two makes ReactJS a powerful front-end library.
