Higher-order components or HOC is the advanced method of reusing the component functionality logic. It simply takes the original component and returns the enhanced component.
Syntax:
const EnhancedComponent = higherOrderComponent(OriginalComponent);
Reason to use Higher-Order component:
- Easy to handle
- Get rid of copying the same logic in every component
- Makes code more readable
Creating React Application:
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Step 1: Create a React application using the following command.
npx create-react-app foldername
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Step 2: After creating your project folder i.e. foldername, move to it using the following command.
cd foldername
Project Structure:
Example 1: Let say, we need to reuse the same logic, like passing on the name to every component.
Name.js
import React from 'react'  const EnhancedComponent = (OriginalComponent) => {     class NewComponent extends React.Component {           // Logic here           render() {             // Pass the callable props to Original component             return <OriginalComponent name="neveropen" />         }     }     // Returns the new component     return NewComponent }   export default EnhancedComponent; |
App.js
import React from "react"; import "./App.css"import EnhancedComponent from './Name'   class App extends React.Component {   render() {     // Call the props from originalComponent     return <h1>{this.props.name}</h1>   } }    // Passed the originalcomponent export default EnhancedComponent(App); |
Output: Here, we pass the name as a prop with the value for calling out from different components.
Example 2: In this example let’s implement some logic. Let’s make a counter app. In HighOrder.js, we pass the handleclick and show props for calling the functionality of the component.
Project Structure:
HighOrder.js
import React from 'react'  const EnhancedComponent = (OriginalComponent) => {     class NewComponent extends React.Component {           constructor(props) {             super(props);             // Set initial count to be 0             this.state = { count: 0 };         }           handleClick = () => {             // Incrementing the count             this.setState({ count: this.state.count + 1 });         }           render() {               // passed a handleclick and count in the originalComponent             // as a props for calling and adding the functionality             return <OriginalComponent                 handleclick={this.handleClick}                 show={this.state.count} />         }     }     // Returns the new component     return NewComponent } // Export main Component export default EnhancedComponent |
App.js
import React from 'react'import "./App.css"// importing HighOrder file import EnhancedComponent from './HighOrder'   class App extends React.Component {   render() {     // Destructuring the props     const { show, handleclick } = this.props       // Calling out the props     return <button onClick={handleclick}>{show}     </button>   } }     export default EnhancedComponent(App); |
Output:
Reference:https://reactjs.org/docs/higher-order-components.html
