how to download file in react js – Download

The Problem:

You are developing a web application using React JS, and you have an API that provides a file URL. When a user clicks a "Download" button, you want to download the file directly to their computer without opening a file preview in a new tab. How can you achieve this functionality in React JS?

The Solutions:

Solution 1: Server-side Download

Instead of attempting to trigger a download directly from the React application, it’s better to create a server-side endpoint that handles the file download. Here’s how you can achieve this:

1. Set up a Server Endpoint:

• Create a route or endpoint on your server that accepts a file URL as a parameter.

2. Handle the Download Request:

• In the server-side code, use appropriate methods (e.g., sendFile or write) to read the file from the specified URL and send it back to the client as a response.

3. Set the Response Headers:

• Ensure that the response headers contain the necessary information to trigger a download. Typically, you would set the Content-Type header to indicate the file type and the Content-Disposition header to specify how the browser should handle the file (e.g., attachment; filename="myfile.txt").

4. Trigger the Download from the Frontend:

• In your React application, when the user clicks the download button, make an HTTP request to the server-side endpoint you created, passing the file URL as a parameter.

5. Handle the Server Response:

• On the frontend, handle the response from the server and prompt the user to save the file locally. Depending on the browser, you might need to use a library or create a custom solution to handle the file download.

This approach ensures that the file is downloaded directly from the server, avoiding any issues with previewing the file in a new tab or browser-specific restrictions.

Solution 2: Using CORS proxy and Blob

This solution involves using a CORS proxy to bypass CORS restrictions and fetch the file from the given URL. Here’s how it works:

1. Fetch File with CORS Proxy:

   • Use a CORS proxy, such as "cors-anywhere.herokuapp.com," to fetch the file securely from the URL.
   • The CORS proxy acts as an intermediary between your app and the file’s origin, allowing you to bypass CORS issues.

2. Convert Response to Blob:

   • Once you receive the file response from the proxy, convert it to a Blob using the response.blob() method. A Blob represents a file-like object that can be downloaded.

3. Create Temporary Blob URL:

   • Create a temporary URL for the Blob using window.URL.createObjectURL(new Blob([blob])). This URL points to the Blob and allows you to download it.

4. Create a Download Link:

   • Create an HTML anchor element (<a> tag) and set its href attribute to the temporary URL created in step 3.
   • Set the download attribute of the link to the desired file name to specify the name of the downloaded file.

5. Append Link to HTML:

   • Append the created link element to the HTML document. This makes it accessible to the browser for downloading.

6. Initiate Download:

   • Trigger the download by calling the click() method on the link element. This action simulates a user click and initiates the file download.

7. Cleanup:

   • Once the download is complete, remove the link element from the HTML to avoid keeping unnecessary elements in the DOM.

By following these steps, you can enable downloads from URLs without opening file previews in a new tab. Please note that this solution requires CORS-enabled servers or a CORS proxy to work effectively.

Solution 3: Utilizing the ‘download’ Attribute

While not specifically related to React, to initiate a file download without opening a preview tab, one can leverage the ‘download’ attribute within the ‘a’ (anchor) HTML element. This attribute prompts the browser to download the file instead of rendering it in a new tab:

<a href='/somefile.txt' download>Click to download</a>

However, it’s important to note that this method may not be supported by all browsers. For more information, refer to the Mozilla Developer Network documentation: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/a

Solution 4: Using React Router to download file

If you are using React Router for routing in your React application, you can utilize the <Link> component to download a file without opening a preview in a new tab. Here’s how you can implement this:

1. Import the <Link> component and the target and download attributes from the react-router-dom package:

import { Link } from 'react-router-dom';

2. In your React component, create a <Link> element with the following attributes:

<Link to="/files/myfile.pdf" target="_blank" download>Download</Link>

• to: Specify the route or URL of the file you want to download. In this example, it’s assumed that the file myfile.pdf is located inside the public folder of your React application, and it’s accessible via the /files route.
• target: Set the target attribute to "_blank". This ensures that the link opens in a new tab or window, preventing the file from being displayed as a preview in the current tab.
• download: The download attribute instructs the browser to download the file instead of displaying it in the browser window.
3. When the user clicks on the Download link, the browser will initiate the download process without opening a new tab for the file preview.

Note: Make sure that the file you are trying to download is served from the same domain as your React application. If the file is hosted on a different domain, you may encounter cross-origin resource sharing (CORS) issues and the download might not work as expected.

Solution 5: Use js-file-download for File Download

To initiate a file download directly from your React application without opening a file preview, you can use the js-file-download library. Here’s how you can implement this solution:

1. Install the js-file-download library:

   npm install js-file-download
   

2. Import the necessary modules:

   import axios from 'axios';
   import fileDownload from 'js-file-download';
   

3. Create a function to handle the file download:

   const handleDownload = (url, filename) => {
     axios.get(url, {
       responseType: 'blob',
     })
     .then((res) => {
       fileDownload(res.data, filename);
     });
   };
   

4. In your React component, add a button or link to trigger the file download:

   <button onClick={() => handleDownload('https://your-website.com/your-image.jpg', 'test-download.jpg')}>Download Image</button>
   

When the user clicks on the button or link, the handleDownload function will be called. This function will make a GET request to the specified URL using axios, and set the responseType to ‘blob’ to retrieve the file as a Blob object.

Once the response is received, it will use the fileDownload function from the js-file-download library to initiate the file download. The fileDownload function takes the Blob object and the desired filename as arguments, and automatically triggers the browser’s download dialog.

This solution allows you to download files直接 from your React application without opening them in a new tab or requiring any additional dependencies.