How to Upload Two Files Using FormData in AJAX with jQuery

Learn how to effectively use jQuery and AJAX to upload two files from different input fields without refreshing the page. This guide breaks down the solution step-by-step.
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Uploading Multiple Files Without Page Refresh: A Comprehensive Guide

When working with file uploads in web applications, it is common to require uploading multiple files simultaneously without refreshing the page. This can enhance user experience significantly. However, implementing such functionality using jQuery, AJAX, and PHP can sometimes pose a challenge. In this post, we'll explore how to effectively append two files from different input file boxes and upload them using AJAX.

The Problem

You've set up an HTML form to allow users to upload two files: a cover image and another file to embed. However, your current implementation is not working as expected when trying to upload both files at once. The primary issue arises from how the files are being appended to the FormData object and how you pass this data in your AJAX request.

Here’s a look at your HTML form structure:

[[See Video to Reveal this Text or Code Snippet]]

While it looks simple, issues often arise in how we manage the file uploads on the JavaScript side.

The Solution

The key to successfully uploading multiple files using AJAX is in creating a single FormData object and appending both files to it before sending it in the AJAX request. Here’s how to do it step by step:

Step 1: Create the FormData Object

You’ll need to create only one instance of the FormData class. This object will hold both files. Therefore, remove any duplicate definitions. Below is the corrected code:

[[See Video to Reveal this Text or Code Snippet]]

Key Points to Note

Using the correct file index: We use [0] for both files to grab the first selected file, ensuring that we're not mistakenly trying to reference a file that doesn't exist.

Single FormData object: Only use one FormData object that includes all your upload data.

AJAX settings: Setting contentType to false is crucial as it prevents jQuery from setting the default Content-Type header, which would break the file upload. Similarly, processData should also be false, which stops jQuery from converting the data into a query string.

Conclusion

Now, with these adjustments to your code, you should be able to upload both files seamlessly without refreshing the page. This technique is not only efficient but also significantly improves the user experience on your web application. If you encounter any issues, make sure to check for errors in your JavaScript console or debug your PHP handling script. Happy coding!