How do I validate file name when I upload file in RadEditor?

[Martin]

I would like to validate file name when I upload document or image in RadEditor. If the file name is not valid, I would like to prompt an error message to user.

Is there any quick and easy way to do this?

I attach a screen shot to help clarify my case.

[Rumen]

Hello Martin,

In order to achieve the requested functionality you should implement a FileSystemContentProvider and
you will be able to get a reference to the uploaded image file, check it name and rename it if needed using the StoreFile method. Here is an example demonstrating how to create a thumbnail, which you can modify to fit your scenario:

using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using Telerik.Web.UI;
using System.Drawing;
using System.IO;


public partial class static_test_editor : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        RadEditor1.ImageManager.ViewPaths = new string[]{"~/"};
        RadEditor1.ImageManager.UploadPaths = new string[] { "~/" };
        RadEditor1.ImageManager.DeletePaths = new string[] { "~/" };
        RadEditor1.ImageManager.ContentProviderTypeName = typeof(myprovider).AssemblyQualifiedName;
    }

    public class myprovider : Telerik.Web.UI.Widgets.FileSystemContentProvider
    {

        public myprovider(HttpContext context, string[] searchPatterns, string[] viewPaths, string[] uploadPaths, string[] deletePaths, string selectedUrl, string selectedItemTag)
            : base(context, searchPatterns, viewPaths, uploadPaths, deletePaths, selectedUrl, selectedItemTag)
        {
        }

        public bool ThumbnailCallback()
        {
            return false;
        }

        public override string StoreFile(UploadedFile file, string path, string name, params string[] arguments)
        {

            string result = base.StoreFile(file, path, name, arguments);

            System.Drawing.Image.GetThumbnailImageAbort myCallback =
                new System.Drawing.Image.GetThumbnailImageAbort(ThumbnailCallback);

            string fileName = Path.Combine(path, name);
            //Create a copy of the image with a different size
            using (System.Drawing.Image originalImage = Bitmap.FromStream(file.InputStream))
            {
                using (System.Drawing.Image thumbnail = originalImage.GetThumbnailImage(300, 300, myCallback, IntPtr.Zero))
                {
                    thumbnail.Save(Context.Server.MapPath(fileName));
                }
            }

            return result;
        }
    }
}

You can also see the following KB article on the subject: Custom FileBrowserContent Provider.

Note that the code above uses FileSystemContentProvider as a base class and not FileBrowserContentProvider. These are two different classes: FileBrowserContentProvider is the base class for all content providers and is the one with the abstract members; FileSystemContentProvider is the default content provider used by the editor - it works with the file system and has implementations for all necessary methods. This is why when you subclass the FileSystemContentProvider class, you do not need to re-define all content provider methods - just the ones you want to change. In the example above we override the StoreFile method, which is called when you upload a new file (image).



Greetings,
Rumen
the Telerik team

[Martin]

Thank you, Rumen. It works for me.

Another question,
How can I prompt user an error message if the file name is not the one we required. I also attach a picture to help explanation.

Thank you.

[Rumen]

Hello Martin,

You will be able to alert an error message using the solution provided in this KB article:
Get reference to the Page object inside a custom FileBrowserContentProvider.

Best wishes,
Rumen
the Telerik team