React 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 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.

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TS JS

Backend API

import React from 'react'; import FileUploader from 'devextreme-react/file-uploader'; const fileExtensions = ['.jpg', '.jpeg', '.gif', '.png']; export default function App() { return ( <div className="main-block"> <div className="file-uploader-block"> <FileUploader multiple={true} uploadMode="useButtons" uploadUrl="https://js.devexpress.com/Demos/NetCore/FileUploader/Upload" allowedFileExtensions={fileExtensions} /> <span className="note">{'Allowed file extensions: '} <span>.jpg, .jpeg, .gif, .png</span> . </span> </div> <div className="file-uploader-block" style={{ float: 'right' }}> <FileUploader multiple={true} uploadMode="useButtons" uploadUrl="https://js.devexpress.com/Demos/NetCore/FileUploader/Upload" maxFileSize={4000000} /> <span className="note">{'Maximum file size: '} <span>4 MB</span> . </span> </div> </div> ); }

import React from 'react'; import FileUploader from 'devextreme-react/file-uploader'; const fileExtensions = ['.jpg', '.jpeg', '.gif', '.png']; export default function App() { return ( <div className="main-block"> <div className="file-uploader-block"> <FileUploader multiple={true} uploadMode="useButtons" uploadUrl="https://js.devexpress.com/Demos/NetCore/FileUploader/Upload" allowedFileExtensions={fileExtensions} /> <span className="note"> {'Allowed file extensions: '} <span>.jpg, .jpeg, .gif, .png</span>. </span> </div> <div className="file-uploader-block" style={{ float: 'right' }} > <FileUploader multiple={true} uploadMode="useButtons" uploadUrl="https://js.devexpress.com/Demos/NetCore/FileUploader/Upload" maxFileSize={4000000} /> <span className="note"> {'Maximum file size: '} <span>4 MB</span>. </span> </div> </div> ); }

import React from 'react'; import ReactDOM from 'react-dom'; import App from './App.tsx'; ReactDOM.render( <App />, document.getElementById('app'), );

import React from 'react'; import ReactDOM from 'react-dom'; import App from './App.js'; ReactDOM.render(<App />, document.getElementById('app'));

<!DOCTYPE html> <html 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" /> <link rel="stylesheet" type="text/css" href="https://cdn3.devexpress.com/jslib/25.1.3/css/dx.light.css" /> <link rel="stylesheet" type="text/css" href="styles.css" /> <script src="https://cdn.jsdelivr.net/npm/core-js@2.6.12/client/shim.min.js"></script> <script src="https://cdn.jsdelivr.net/npm/systemjs@0.21.3/dist/system.js"></script> <script type="text/javascript" src="config.js"></script> <script type="text/javascript"> System.import("./index.tsx"); </script> </head> <body class="dx-viewport"> <div class="demo-container"> <div id="app"></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; }