Last Updated: 19 Oct 2021 15:41 by ADMIN
Release R3 2021 SP1
Created on: 18 Oct 2021 10:38
Category: UI for WinForms
Type: Bug Report
RadRichTextEditor: Built-in spellchecking is not working in .NET Core
1. Create a new windows forms .net 5.0 project

2. Add a richtexteditor control to the form

3. Set IsSpellCheckingEnabled = true

4. Run the project, type invalid word in text box.  The text is not spell-checked.
1 comment
Posted on: 18 Oct 2021 10:40

Hi Bob,

A possible workaround is to explicitly load a dictionary for the "en-US" culture: 

namespace RteSpellcheckNetCore
    public partial class Form1 : Form
        public Form1()

            Stream tdfFileStream = typeof(Form1).Assembly.GetManifestResourceStream("RteSpellcheckNetCore.en-US.tdf");
            RadDictionary dictionary = new RadDictionary();
            ((DocumentSpellChecker)this.radRichTextEditor1.SpellChecker).AddDictionary(dictionary, new CultureInfo("en-US"));


Here you can download dictionaries for different cultures: Then you will need to embed the downloaded file as a resource in your project.

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