WelcomeMessage component, when rendered, will display a heading and a paragraph with a welcome message. You can think of JSX as a way of describing the UI structure with a syntax that closely resembles HTML.
State and Props
Two key concepts in React are state and props. State is the internal data of a component, while props are the external data passed to it from its parent component.
When a component's state or props change, React automatically re-renders the component, ensuring the UI is always up to date. This makes it easy to create dynamic and interactive UIs without having to manually update the DOM.
State is managed within a component and can be initialized and updated using the
useState hook in functional components or the
setState method in class components. Here's a simple example using the
In this example, we've created a
Counter component that manages its own state, allowing it to keep track of how many times the button has been clicked.
Props, short for properties, are used to pass data from a parent component to its children. Here's a simple example of passing props:
In this example, the
App component renders two
Greeting components, each with a different
name prop. The
Greeting component then displays a personalized message based on the
name prop it receives.
React is a powerful and versatile library that has taken the web development world by storm. By understanding its core concepts, such as components, JSX, state, and props, you can unlock the full potential of React to create dynamic and interactive user interfaces. Now that you've been introduced to React, it's time to dive deeper and start building awesome web applications!
What is React and why is it popular?
Can you explain the basic structure of a React component?
React.Component. It usually has a
render method that returns JSX (a syntax extension that looks similar to HTML) to describe what the component should look like. Here's a simple example of a functional React component:
How do I use a React component in another component?
To use a React component in another component, first import the desired component and then include it as a JSX tag within the parent component's JSX. Here's an example of how to use the
HelloWorld component we defined earlier inside another component:
What are props in React and how do I use them?
Props (short for "properties") are a way to pass data from a parent component to a child component. To use props, define the desired attributes on the child component JSX tag in the parent component, and then access those attributes as properties of the
props object in the child component. Here's an example:
In this example, we're passing a
name prop from the
App component to the
Greeting component. The
Greeting component then uses the
name prop to display a personalized greeting.