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How to render a variable in html ReactJS

Getting Started

Rendering a variable in HTML using ReactJS might seem complicated at first, but with a little practice, it becomes pretty simple. Let's break this down step by step, and see how we can do it. But first, let's understand what 'rendering a variable' means.

Rendering a variable is just a fancy way of saying "showing a variable". A variable is like a small box where we can store something, and rendering is like opening that box and showing what's inside.

Understanding JSX

ReactJS uses a special syntax called JSX, which allows us to write HTML-like code in our JavaScript code. In other words, JSX allows us to mix HTML and JavaScript together. This is great because it allows us to write more readable and expressive code. Here's what JSX looks like:

const element = <h1>Hello, world!</h1>;

As you can see, it looks like HTML, but it's actually JavaScript.

Rendering a Variable in JSX

Now, let's see how to render a variable in JSX. To render a variable, we need to put the variable inside curly brackets {}. This tells React that we want to treat the content inside the curly brackets as JavaScript, not as plain text. Here's how to do it:

const name = 'John Doe';
const element = <h1>Hello, {name}!</h1>;

In this example, name is a variable that holds the string 'John Doe'. When React sees {name}, it replaces it with the value of the name variable. So, the output of this code would be: "Hello, John Doe!".

Rendering a Variable in a Component

In React, we usually work with components. A component is like a building block of a React application. It's a piece of code that can be reused multiple times.

Let's create a simple component that renders a variable. In this case, we'll create a Welcome component that displays a welcome message to a user:

function Welcome(props) {
  return <h1>Hello, {props.name}!</h1>;
}

In this example, props is an object that holds all the properties (or "props") passed to the component. We're passing a name prop to the Welcome component, and then we're using {props.name} to render the value of the name prop.

We can use the Welcome component like this:

const element = <Welcome name="John Doe" />;

In this case, "John Doe" is the value of the name prop. So, the output of the Welcome component would be: "Hello, John Doe!".

Rendering Multiple Variables

We can also render multiple variables in JSX. To do this, we just need to put each variable inside its own set of curly brackets:

const firstName = 'John';
const lastName = 'Doe';
const element = <h1>Hello, {firstName} {lastName}!</h1>;

In this example, we have two variables: firstName and lastName. We're rendering both variables in the h1 element. So, the output of this code would be: "Hello, John Doe!".

Conclusion

Rendering a variable in ReactJS is like telling a story. You have characters (the variables) and you want to integrate them into your narrative (the HTML). You just need to remember to put them inside curly brackets so that React knows they're part of the script and not just background noise. Keep practicing and soon it will become second nature. Remember, every great coder started out as a beginner, persistent practice is the key. Happy coding!