react react-dom Why react-dom is separated from react Example: Conclusion

In React, when you want to access props inside attribute values, you must use curly braces ({}) to embed JavaScript expressions—including prop values—within JSX. Here, name is a prop, and we access it inside the JSX using {name}. Accessing props inside attribute values (in quotes) When setting an attribute using a prop, do not use…

React.PropTypes.shape is used in React to validate the shape of an object prop—that is, to specify what properties the object should have, and what types each property should be. Note: PropTypes is no longer under React.PropTypes in newer React versions. Instead, you must import it from the prop-types package. Example: Validating object shape with PropTypes.shape…

In React, keyed fragments are a way to assign a key to a React.Fragment, which is useful when rendering a list of fragments inside a loop. What is a Fragment? A Fragment lets you group multiple elements without adding extra nodes to the DOM. It looks like this: This is equivalent to: What is a…

To programmatically trigger a click event in React, you can use the useRef hook to reference a DOM element or component, and then call its .click() method. Here’s a complete example: Example: Programmatically triggering a button click Explanation:

In React, hooks must not be called conditionally or inside event handlers directly — they must always be called at the top level of a functional component or inside a custom hook. However, you can use state to control when the effect of a hook should happen. Here’s how to trigger logic in a hook…

In React, prop validation is used to ensure that components receive props of the expected type and shape. This helps catch bugs early by throwing warnings in development if props are missing or invalid. React provides a built-in library called prop-types for validating props. Step-by-Step: How to Apply Validation on Props Install prop-types Package If…

In React, the children prop is a special built-in prop automatically passed to every component. It represents the content between the opening and closing tags of a component. It enables component composition, allowing you to build flexible and reusable UI structures. Basic Usage Example: Output: Explanation: Why Use children? 1. Component Composition 2. Reduces Prop…

A Higher-Order Component (HOC) is a function that takes a component and returns a new enhanced component. This is a design pattern in React for reusing component logic. Think of it as a “component factory” — a function that takes a component, enhances it, and returns a new component with added features or behavior. Why…

In React, to listen to state changes in functional components, the recommended way is to use the useEffect hook. React does not provide a direct observer-like system for watching state changes — instead, you can react to them with side effects. 1. Use useEffect to Listen to State Changes How it works: 2. Listen to…