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Roktim Kamal Senapoty
Roktim Kamal Senapoty

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The Secret to Mastering React JS: Hone Your Skills with these JavaScript Topics First

React JS is a JavaScript library that helps developers 👩‍💻 build dynamic and interactive web applications 💻. It simplifies the process of creating user interfaces 🖥️ by breaking them down into reusable components ♻️. These components can be thought of as building blocks 🏗️ that can be combined to create complex web pages 🌐. React efficiently updates 🔄 and renders these components, resulting in fast ⚡ and responsive applications 📱. It's a powerful tool 🔧 for beginners in web development to create engaging user interfaces with ease 😄👍.

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Before diving into React, it's important to have a solid understanding of JavaScript. Here are some essential concepts and topics to learn:

1.Variables

You can declare variables using "var", "let", or "const". Here are some examples:

Variables

"var" has been used earlier, but "let" and "const" are newer and offer advantages such as block-scoping for "let" and immutability for "const".

2.Functions and Arrow Functions

In JavaScript, functions are a fundamental concept that allow you to define a block of code that can be executed multiple times with different parameters. There are two ways to define functions in JavaScript: using the "function" keyword or using arrow functions.

Here is an example of a function defined using the "function" keyword:

Functions and Arrow Functions

In this example, we define a function called "multiply" that takes two parameters, "a" and "b", and returns their product. We then call the function with the arguments 2 and 3, and log the result to the console.

Here is the same function defined using an arrow function:

Functions and Arrow Functions

In this example, we define a function called "multiply" using the arrow function syntax. The arrow function takes two parameters, "a" and "b", and returns their product. We then call the function with the arguments 2 and 3, and log the result to the console.

One key difference between the two syntaxes is that arrow functions have a more concise syntax and a different behavior for the "this" keyword. Arrow functions do not have their own "this" context, so they inherit the "this" value from the enclosing lexical context. This can make arrow functions useful in certain situations, such as when defining callbacks.

3.Arrays (and the .map() function)

Arrays are used in JavaScript to store collections of data. Here is an example:

Arrays

You can access individual array elements using square bracket notation and the index of the element. You can add elements to an array using the "push" method. Here is an example:

Arrays

Arrays have many built-in methods such as "map", "filter", and "reduce" that allow you to transform and manipulate the data in the array. Here is an example of using the "map" method to transform an array:

Arrays

4.Objects

Objects in JavaScript are used to store collections of related data and functionality. Here is an example:

Objects

You can add properties to an object using dot notation or square bracket notation. Here is an example:

Objects

Objects can also be used to create classes and instances of those classes, which is a key feature of object-oriented programming in JavaScript.

5.Template literals

Template literals are a feature in JavaScript that allow you to embed expressions and variables into string literals using backticks (`) instead of single or double quotes. Here is an example:

Template literals

In this example, we define two variables called "name" and "age". We then use a template literal to embed these variables into a string using the ${} syntax. When we log this string to the console, the values of the variables are interpolated into the string.

Template literals can also span multiple lines and include expressions and functions:

Template literals

In this example, we use template literals to construct strings that include expressions for computing the square of a number and getting the current date. Note that template literals can also contain regular strings and escape characters just like normal strings.

Overall, template literals are a powerful and convenient way to construct complex strings in JavaScript that include dynamic values and expressions.

6.Ternary operators

Ternary operators are a shorthand way to write an if-else statement in JavaScript. Here is an example:

Ternary operators

The syntax of a ternary operator is as follows:

Ternary operators

You can use ternary operators to assign values to variables or to return values from functions:

Ternary operators

In this example, we define a function called "getGreeting" that uses a ternary operator to assign a greeting message to a variable called "greeting" based on the value of the "time" parameter. We then return the value of the "greeting" variable. When we call the function with different values of "time", we get different greetings.

7.ES Modules and Import / Export Syntax

ES Modules allow you to modularize your code and import/export functionality between modules. Here is an example:

ES Modules and Import / Export Syntax

In this example, we define a function in a module called "module.js" and export it using the "export" keyword. We then import this function into another module called "main.js" using the "import" keyword and curly braces {}. We can then call the function in "main.js" and get the sum of two numbers.

You can also use the "export default" syntax to export a single value from a module without specifying a name:

ES Modules and Import / Export Syntax

In this example, we define a function and export it as the default value of the module using the "export default" syntax. We then import this default value using the "import" keyword without curly braces {}. We can then call the function in "main.js" and get the sum of two numbers.


Congratulations 🎉, you've made it to the end of this blog! I hope you found the information useful 💡 and informative. Thank you for taking the time to read this 📚 and I encourage you to continue learning and exploring the world of JavaScript 🌐. 🔥 Follow for more..

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Top comments (14)

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nadjib_os profile image
nadjibOs

My pillars to mastering Reactjs are:

  1. State Management
  2. Data fetching
  3. When react re renders
  4. Code design
  5. Folder structure
  6. Errors Handling
  7. Types

I think if you master these topics, you can safely say that you are a Reactjs pro.

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mlodovico profile image
Murilo Lodovico

Great notes man! I think it would be interesting make more examples of “this” context in functions and arrow functions to be more paupable your idea and explanations. 🤘🤘

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roktim32 profile image
Roktim Kamal Senapoty

Sure 😁

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akhilasingapuram profile image
akhilasingapuram

Informative and interesting. In a simple way, the concepts are explained. Thank you very much!

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roktim32 profile image
Roktim Kamal Senapoty

Thank You! Follow for more of these

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akhilasingapuram profile image
akhilasingapuram

Sure!

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andrewrgarcia profile image
Andrew Garcia

After dabbling on C++ for some time, all code looks like it was written by a high schooler

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roktim32 profile image
Roktim Kamal Senapoty

Haha Yes!

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kunj63 profile image
kunj patel

Very useful bro👍

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roktim32 profile image
Roktim Kamal Senapoty

Thank you bro🚀

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vickey74238426 profile image
Vickey

I think we also do need to understand how asynchronous js works before diving into react.

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roktim32 profile image
Roktim Kamal Senapoty

Thank You for the suggestion. I will add that too

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taysongermano profile image
Tyson Monteiro

Good article brother! I would add "short-circuit" as well

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roktim32 profile image
Roktim Kamal Senapoty

Thank You! I will add that too!