JavaScript/jQuery File Uploader - Validation

This demo shows how to use the allowedFileExtensions and maxFileSize properties to limit the maximum size and specify file extensions that the JavaScript FileUploader accepts. Note that demonstrated validation is client-side — you should implement the server-side validation. You can see an example under the FileUploaderController tab in the ASP.NET MVC version of this demo.

Was this demo helpful?

Thank you!

Feel free to share demo-related thoughts here.
If you have technical questions, please create a support ticket in the DevExpress Support Center.

Thank you for the feedback!

Backend API

$(() => { $('#file-uploader-images').dxFileUploader({ multiple: true, uploadMode: 'useButtons', uploadUrl: 'https://js.devexpress.com/Demos/NetCore/FileUploader/Upload', allowedFileExtensions: ['.jpg', '.jpeg', '.gif', '.png'], }); $('#file-uploader-max-size').dxFileUploader({ multiple: true, uploadMode: 'useButtons', uploadUrl: 'https://js.devexpress.com/Demos/NetCore/FileUploader/Upload', maxFileSize: 4000000, }); });

<!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml" lang="en"> <head> <title>DevExtreme Demo</title> <meta http-equiv="X-UA-Compatible" content="IE=edge" /> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=5.0" /> <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script> <script>window.jQuery || document.write(decodeURIComponent('%3Cscript src="js/jquery.min.js"%3E%3C/script%3E'))</script> <link rel="stylesheet" type="text/css" href="https://cdn3.devexpress.com/jslib/24.1.6/css/dx.light.css" /> <script src="js/dx.all.js"></script> <link rel="stylesheet" type="text/css" href="styles.css" /> <script src="index.js"></script> </head> <body class="dx-viewport"> <div class="demo-container"> <div class="main-block"> <div class="file-uploader-block"> <div id="file-uploader-images"></div> <span class="note">Allowed file extensions: <span>.jpg, .jpeg, .gif, .png</span>.</span> </div> <div class="file-uploader-block" style="float: right"> <div id="file-uploader-max-size"></div> <span class="note">Maximum file size: <span>4 MB</span>.</span> </div> </div> </div> </body> </html>

.file-uploader-block { width: 350px; float: left; } .note { font-size: 10pt; color: #484848; margin-left: 9px; } .note > span { font-weight: 700; } .main-block { max-width: 900px; min-width: 700px; }