What is jsx

JSX (JavaScript XML) is a syntax extension for JavaScript, commonly used with React to describe what the UI should look like. It allows you to write HTML structures within JavaScript code, making the code more readable and expressive. Here’s an overview of JSX in the context of React:

Key Features of JSX:

HTML-like Syntax: JSX allows you to write HTML-like code directly within JavaScript files. For example:


const element = 

Hello, world!

;

This code creates a React element that represents an <h1> element with the text “Hello, world!”.

Embedded Expressions: You can embed JavaScript expressions within JSX using curly braces {}. For example:


const name = 'John';
const element = 

Hello, {name}!

;

This will render as <h1>Hello, John!</h1>.

Components: JSX is often used to define React components. Components can be functions or classes that return JSX:


function Welcome(props) {
  return 

Hello, {props.name}

; }

This function component takes a name prop and renders it within an <h1> element.

Attributes: You can use attributes in JSX similarly to HTML. However, in JSX, attribute names follow camelCase convention instead of kebab-case. For example:


const element = <img src="logo.png" className="logo" alt="Logo" />;

In this example, we use className attribute instead of class in jsx file in Reactjs.

Example2:


<h1 style={{color:"white", backgroundColor:"red"}}>Hello Css Example</h1>

In this example, we use style attribute has backgroundColor property in a camelCase in jsx in Reactjs.

How JSX Works:

JSX is not valid JavaScript by itself. Browsers cannot read it directly. Therefore, it needs to be transpiled to regular JavaScript using tools like Babel. During the build process, Babel transforms JSX into React.createElement() calls:


const element = <h1>Hello, world!</h1>;
// Transpiles to:
const element = React.createElement('h1', null, 'Hello, world!');
Advantages of JSX:

Readability: JSX makes the structure of the component more understandable and similar to HTML, making it easier to visualize the UI structure.

Integration: Embedding JavaScript expressions directly within the markup allows for dynamic content rendering and complex UI interactions.

Componentization: JSX promotes the creation of reusable UI components.