2021 Fetch — React Download

In , downloading a file using the Fetch API is the standard approach for handling secure or dynamic file requests. While a simple anchor tag works for public assets, fetch allows you to include authentication headers (like JWT) and handle complex responses like Blobs or ArrayBuffers without leaving your application. How to Implement "React Download Fetch"

Here is a robust function to handle file downloads in a React handler: javascript

: Unlike standard links, fetch allows you to pass Authorization headers . react download fetch

const handleDownload = async (fileUrl, fileName) => { try { const response = await fetch(fileUrl, { method: 'GET', headers: { // Essential if your API requires authentication 'Authorization': `Bearer ${token}`, }, }); if (!response.ok) throw new Error('Download failed'); // 1. Convert response to a Blob (Binary Large Object) const blob = await response.blob(); // 2. Create a temporary URL for the Blob const url = window.URL.createObjectURL(blob); // 3. Create a hidden tag and click it const link = document.createElement('a'); link.href = url; link.setAttribute('download', fileName); document.body.appendChild(link); link.click(); // 4. Clean up: remove the link and revoke the URL link.parentNode.removeChild(link); window.URL.revokeObjectURL(url); } catch (error) { console.error("Error downloading file:", error); } }; Use code with caution. Why Use Fetch Over Simple Links?

: fetch helps navigate Cross-Origin Resource Sharing (CORS) policies by allowing you to handle the response stream directly. In , downloading a file using the Fetch

: You can extract the filename from the server's Content-Disposition header rather than hardcoding it in the UI.

: It is perfect for non-JSON responses like PDFs, images, or ZIP files. Key Concepts to Know const handleDownload = async (fileUrl, fileName) => {

The most reliable method involves fetching the file as a binary , creating a temporary URL for it, and programmatically triggering a download via a hidden anchor tag. 1. The Core Implementation