Effective Loading and Error Handling in React Applications

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

function DataFetchingComponent() {
  const [data, setData] = useState(null);
  const [loading, setLoading] = useState(true);  // Loading state
  const [error, setError] = useState(null);      // Error state

  useEffect(() => {
    const fetchData = async () => {
      setLoading(true);
      setError(null); // Reset error before starting the request

      try {
        const response = await fetch('https://api.example.com/data');
        if (!response.ok) {
          throw new Error('Failed to fetch data');  // If response is not OK, handle it
        }
        const result = await response.json();
        setData(result);  // Set data after successful fetch
      } catch (err) {
        setError(err.message);  // Catch any errors and set error state
      } finally {
        setLoading(false);  // Always turn off loading state when done
      }
    };

    fetchData();
  }, []);  // Empty array means it runs once when the component mounts

  if (loading) {
    return <p>Loading...</p>;  // Show loading state
  }

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

  return (
    <div>
      {/* Render the fetched data when available */}
      <h1>Data Fetched Successfully</h1>
      <pre>{JSON.stringify(data, null, 2)}</pre>
    </div>
  );
}

export default DataFetchingComponent;