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useMemo in React with sample

useMemo is a hook in React that allows you to optimize the performance of your component by memorizing a value that is expensive to calculate. The hook takes two arguments: a function that calculates the value, and a list of dependencies. The memorized value is recalculated only if one of the dependencies has changed. Here’s a simple example of using useMemo

import React, { useState, useMemo } from 'react';

function Example({ data }) {

const [filter, setFilter] = useState('');

// This calculation is expensive, so we only want to do it if the

// filter or data has changed.

const filteredData = useMemo(

() => data.filter(item => item.includes(filter)),

[data, filter]

);

return (

<div>

<input value={filter} onChange={e => setFilter(e.target.value)} />

<ul>

{filteredData.map(item => (

))}

</ul>

</div>

);

}

In this example,… ادامه »useMemo in React with sample

useEffect in React

useEffect is a Hook in React that allows you to run some code after rendering has completed. This is useful for scenarios where you need to perform side effects, such as making an API call or updating the title of a document, after a component has been updated Here’s an example of how useEffect can be used to fetch data from an API and update… ادامه »useEffect in React

use axios in react with sample

Axios is a popular library for making HTTP requests in JavaScript, and it’s often used in React projects to retrieve data from APIs and other server-side resources. Here’s an example of how you can use Axios in a React component to fetch data from a server:

import React, { useState, useEffect } from 'react';

import axios from 'axios';

const Example = () => {

const [data, setData] = useState([]);

const [error, setError] = useState(null);

const [loading, setLoading] = useState(false);

useEffect(() => {

const fetchData = async () => {

setLoading(true);

setError(null);

try {

const response = await axios.get('https://api.example.com/data');

setData(response.data);

} catch (err) {

setError(err);

} finally {

setLoading(false);

}

};

fetchData();

}, []);

if (loading) return <p>Loading...</p>;

if (error) return <p>Error: {error.message}</p>;

return (

<ul>

{data.map(item => (

<li key={item.id}>{item.title}</li>

))}

</ul>

);

};

export default Example;

In this example, we use the useEffect hook to fetch data from an API when the component is… ادامه »use axios in react with sample

better architecture for react project

There is no one-size-fits-all answer to this question, as the best architecture for a React project will depend on a number of factors, including the size and complexity of the project, the requirements and constraints of the project, and the preferences and expertise of the development team. However, there are some general principles that can be helpful in guiding the design of a well-structured React… ادامه »better architecture for react project