Best Practices for Using AJAX in React Applications

When developers ask about AJAX in React, they often hear that React is merely a view library without built‑in networking, which is true but unhelpful for fetching data in components.

The article presents four practical methods for integrating AJAX with React and advises selecting the appropriate technique based on application size, complexity, and existing libraries.

1. Root Component method : Create a single top‑level component that performs all AJAX requests, stores responses in its state, and passes data to child components via props. Suitable for simple or small apps with shallow component trees and no Redux or Flux.

2. Container Component method : Use dedicated container components to fetch data and supply it to presentational components through props. This scales better for deeper component trees, multiple data sources, and when most components do not need server data.

3. Redux Async Actions : When using Redux (or Flux), place AJAX calls in asynchronous action creators rather than inside React components, typically using the fetch() API. Ideal for projects already employing Redux or Flux for state management.

4. Relay : Leverage GraphQL and Relay to declare component data requirements; Relay automatically fetches and injects the data via props. Best for large applications with a single GraphQL server and sufficient upfront knowledge of Relay and GraphQL.

The article also highlights two anti‑patterns to avoid: embedding AJAX logic directly in presentational components, which violates separation of concerns, and using ReactDOM.render() to manually re‑render the UI after data changes.

In conclusion, React applications should treat AJAX as a separate module, choosing the method that matches the project's architecture and complexity.