Froala Editor v4.2.1 is HereLEARN MORE

Skip to content


Image Upload

The following code example illustrates how to handle image upload on your server using .Net Web MVC as a server-side language. For step by step explanation of the upload flow see image upload concept.


The main index page.

<!DOCTYPE html>
<meta charset="utf-8">
<!-- Include Editor style. -->
<link href="[email protected]/css/froala_editor.pkgd.min.css" rel="stylesheet" type="text/css" />

<!-- Include Editor JS files. -->
<script type="text/javascript" src="[email protected]//js/froala_editor.pkgd.min.js"></script>

<div class="sample">
<h2>Image upload example.</h2>
<textarea id="edit" name="content"></textarea>

<!-- Initialize the editor. -->
new FroalaEditor('#edit', {
// Set the image upload URL.
imageUploadURL: '/UploadFiles',

imageUploadParams: {
id: 'my_editor'


HomeController.cs file is the default controller that will be used in this example to define the upload part. The uploads directory will be automatically created if it dose not exist under wwwroot/upload/. The root directory must be write available otherwise the upload directory will not be created.

The HomeController will manage the request and the upload part, so you should define the following functions in this file. After processing the uploaded image, if it passes the validation, the server will respond with a JSON object containing a link to the uploaded image.

E.g.: {"link":"http://server_address/upload/name_of_file"}.

public class HomeController : Controller
public ActionResult UploadFiles()
if (Request.Files["file"] != null)
HttpPostedFileBase MyFile = Request.Files["file"];

// Setting location to upload files
string TargetLocation = Server.MapPath("~/Files/");

if (MyFile.ContentLength > 0)
// Get File Extension
string Extension = Path.GetExtension(MyFile.FileName);

// Determining file name. You can format it as you wish.
string FileName = Path.GetFileName(MyFile.FileName);
FileName = Guid.NewGuid().ToString().Substring(0, 8);

// Determining file size.
int FileSize = MyFile.ContentLength;

// Creating a byte array corresponding to file size.
byte[] FileByteArray = new byte[FileSize];

// Basic validation for file extension
string[] AllowedExtension = { ".gif", ".jpeg", ".jpg", ".png", ".svg", ".blob" };
string[] AllowedMimeType = { "image/gif", "image/jpeg", "image/pjpeg", "image/x-png", "image/png", "image/svg+xml"};

if (AllowedExtension.Contains(Extension) && AllowedMimeType.Contains(MimeMapping.GetMimeMapping(MyFile.FileName)))
// Posted file is being pushed into byte array.
MyFile.InputStream.Read(FileByteArray, 0, FileSize);

// Uploading properly formatted file to server.
MyFile.SaveAs(TargetLocation + FileName + Extension);
string json = "";
Hashtable resp = new Hashtable();
string urlPath = MapURL(TargetLocation) + FileName + Extension;

// Make the response an json object
resp.Add("link", urlPath);
json = JsonConvert.SerializeObject(resp);

// Clear and send the response back to the browser.
Response.ContentType = "application/json; charset=utf-8";
// Handle validation errors

catch (Exception ex)
// Handle errors
return View();

// Convert file path to url
private string MapURL(string path)
string appPath = Server.MapPath("/").ToLower();
return string.Format("/{0}", path.ToLower().Replace(appPath, "").Replace(@"\", "/"));

Do you think we can improve this article? Let us know.