How to Call API in a Loop in React

How to Call API in a Loop in React

When working with React, you may come across situations where you need to call an API in a loop. This could be for fetching multiple data points or performing batch operations. In this blog post, we will explore different approaches to achieve this in a React application.

1. Using async/await and a for loop

One way to call an API in a loop is by using the async/await syntax along with a for loop. This approach allows you to make API calls sequentially and wait for each response before making the next call.

Here’s an example of how you can implement this:

{`async function fetchData() {
  const data = [];
  
  for (let i = 0; i < 5; i++) {
    const response = await fetch('https://api.example.com/data/' + i);
    const result = await response.json();
    data.push(result);
  }
  
  console.log(data);
}

fetchData();`}

In this example, we are making 5 API calls sequentially using a for loop. The fetch function is used to make the API call, and response.json() is used to parse the response as JSON. The data from each response is then pushed into an array.

2. Using Promise.all and map

Another approach to call an API in a loop is by using Promise.all along with the map function. This approach allows you to make API calls in parallel and wait for all the responses to be resolved.

Here's an example of how you can implement this:

{`async function fetchData() {
  const urls = ['https://api.example.com/data/1', 'https://api.example.com/data/2', 'https://api.example.com/data/3', 'https://api.example.com/data/4', 'https://api.example.com/data/5'];
  
  const responses = await Promise.all(urls.map(url => fetch(url)));
  const data = await Promise.all(responses.map(response => response.json()));
  
  console.log(data);
}

fetchData();`}

In this example, we have an array of URLs that we want to call in parallel. The map function is used to create an array of promises, and Promise.all is used to wait for all the promises to be resolved. Finally, we use response.json() to parse the response as JSON.

These are two common approaches to call an API in a loop in React. You can choose the one that best suits your requirements and application architecture.

Remember to handle errors and edge cases appropriately when making API calls in a loop. Also, consider the performance implications of making multiple API calls and ensure that your application can handle the increased load.

Happy coding!