Read-Only Mode and Preview Mode: Programmatic Control

The WinForms HTML Editor exposes three operating modes through a single property on the control. Most "how do I make the editor read-only?" tickets boil down to picking the right mode and, where needed, hooking the click event so anchors still navigate.

The three editor modes

The mode is held in the EditorMode property of type SpiceLogic.HtmlEditor.Abstractions.EditorModes. The enum has three values:

Value	What the user sees	Editing
`WysiwygDesign`	Rendered HTML with the caret and spell-check underline.	Full WYSIWYG editing. Typing, paste, drag & drop, formatting commands all work.
`HtmlEdit`	The raw HTML source in a monospace textarea.	The user edits markup directly. Formatting commands targeted at a rendered DOM are no-ops here.
`ReadOnlyPreview`	Rendered HTML exactly as a browser would show it, with no caret or selection chrome.	None. Keystrokes are ignored. Hyperlinks become live (see below).

Switching mode from C#

Set the property at any time after the editor has loaded. The control fires EditorModeChanged after the swap is complete so you can update surrounding UI (status bar, custom ribbon, menu radio buttons) in one place.

C#VB.NET

using SpiceLogic.HtmlEditor.Abstractions;

// Switch to Preview (read-only render) on a button click:
private void btnPreview_Click(object sender, EventArgs e)
{
    htmlEditor1.EditorMode = EditorModes.ReadOnlyPreview;
}

// Be notified after the mode actually changes:
htmlEditor1.EditorModeChanged += (s, e) =>
{
    statusLabel.Text = $"Mode: {htmlEditor1.EditorMode}";
    toolbar1.Visible = htmlEditor1.EditorMode == EditorModes.WysiwygDesign;
};

Imports SpiceLogic.HtmlEditor.Abstractions

End Sub
' Switch to Preview (read-only render) on a button click:
Private Sub btnPreview_Click(sender As Object, e As EventArgs)
    htmlEditor1.EditorMode = EditorModes.ReadOnlyPreview

    ' Be notified after the mode actually changes:

The event also fires when the user clicks the built-in Source / Preview toolbar buttons, so the same handler covers both code-driven and user-driven changes.

Read-only without leaving Design view

If you want the editing surface to stay rendered exactly as it is - for example after Save - but to stop accepting input, do not switch modes. Set htmlEditor1.Enabled = false. That disables the surface, the toolbar and the keyboard in one step, and re-enabling restores the caret where the user left it.

C#VB.NET

htmlEditor1.Enabled = false; // lock
htmlEditor1.Enabled = true; // unlock

htmlEditor1.Enabled = False ' lock
htmlEditor1.Enabled = True ' unlock

Allowing link clicks in Preview

In ReadOnlyPreview the editor renders anchors as live links. By default, a click opens the href in the system default browser (see "Opening a hyperlink in the default browser instead of MSIE" for the background on why this changed). To intercept the click and run your own logic - in-app navigation, analytics, a confirmation prompt - subscribe to HtmlElementClicked and check the element type:

C#VB.NET

using SpiceLogic.HtmlEditor.Abstractions;
using SpiceLogic.HtmlEditor.WinForms.Models.BOs.EditorEventArgs;

htmlEditor1.HtmlElementClicked += (s, e) =>
{
    if (htmlEditor1.EditorMode != EditorModes.ReadOnlyPreview)
        return;
    if (e.ElementType != HtmlElementTypes.Hyperlink)
        return;
    string href = e.ClickedElement.GetAttribute("href");
    MyAppRouter.Navigate(href); // your own handler
};

Imports SpiceLogic.HtmlEditor.Abstractions
Imports SpiceLogic.HtmlEditor.WinForms.Models.BOs.EditorEventArgs

htmlEditor1.HtmlElementClicked += Sub(s, e)
                                      If htmlEditor1.EditorMode IsNot EditorModes.ReadOnlyPreview Then Return
                                      If e.ElementType IsNot HtmlElementTypes.Hyperlink Then Return
                                      Dim href As String = e.ClickedElement.GetAttribute("href")
                                      MyAppRouter.Navigate(href) ' your own handler

Your handler runs before the editor's built-in shell call. If you handle the URL yourself, the OS handoff effectively becomes a no-op because nothing in your code requested it.

Hiding the toolbar in read-only mode

The two factory toolbars are exposed as Toolbar1 and Toolbar2 (both ToolStrip instances). Toggle their Visible property from EditorModeChanged so the chrome follows the mode:

C#VB.NET

htmlEditor1.EditorModeChanged += (s, e) =>
{
    bool editing = htmlEditor1.EditorMode == EditorModes.WysiwygDesign;
    htmlEditor1.Toolbar1.Visible = editing;
    htmlEditor1.Toolbar2.Visible = editing;
    htmlEditor1.ToolbarFooter.Visible = editing;
};

htmlEditor1.EditorModeChanged += Sub(s, e)
                                     Dim editing As Boolean = htmlEditor1.EditorMode Is EditorModes.WysiwygDesign
                                     htmlEditor1.Toolbar1.Visible = editing
                                     htmlEditor1.Toolbar2.Visible = editing
                                     htmlEditor1.ToolbarFooter.Visible = editing

Remembering the user's last mode across sessions

Persist the enum value as its name (a string), not its integer - the int values are an implementation detail and could shift if new modes are ever added. Restore on load after the editor has finished initialising:

C#VB.NET

// On form closing:
Properties.Settings.Default.LastEditorMode = htmlEditor1.EditorMode.ToString();
Properties.Settings.Default.Save();
// On form load:
if (Enum.TryParse<EditorModes>(Properties.Settings.Default.LastEditorMode, out var saved))
    htmlEditor1.EditorMode = saved;

' On form closing:
Properties.Settings.[Default].LastEditorMode = htmlEditor1.EditorMode.ToString()
Properties.Settings.[Default].Save()
' On form load:
Dim saved = Nothing
If [Enum].TryParse(Of EditorModes)(Properties.Settings.[Default].LastEditorMode, saved) Then htmlEditor1.EditorMode = saved

Full example - preview-with-link-handling and Escape to go back

C#VB.NET

using System;
using System.Windows.Forms;
using SpiceLogic.HtmlEditor.Abstractions;
using SpiceLogic.HtmlEditor.WinForms;
using SpiceLogic.HtmlEditor.WinForms.Models.BOs.EditorEventArgs;

public partial class MainForm : Form
{
    public MainForm()
    {
        InitializeComponent();
        htmlEditor1.EditorModeChanged += OnEditorModeChanged;
        htmlEditor1.HtmlElementClicked += OnHtmlElementClicked;
        htmlEditor1.KeyDown += OnEditorKeyDown;
    }

    private void btnPreview_Click(object sender, EventArgs e)
    {
        htmlEditor1.EditorMode = EditorModes.ReadOnlyPreview;
    }

    private void OnEditorModeChanged(object sender, EventArgs e)
    {
        bool editing = htmlEditor1.EditorMode == EditorModes.WysiwygDesign;
        htmlEditor1.Toolbar1.Visible = editing;
        htmlEditor1.Toolbar2.Visible = editing;
        statusLabel.Text = $"Mode: {htmlEditor1.EditorMode}";
    }

    private void OnHtmlElementClicked(object sender, HtmlElementClickedEventArgs e)
    {
        if (htmlEditor1.EditorMode != EditorModes.ReadOnlyPreview)
            return;
        if (e.ElementType != HtmlElementTypes.Hyperlink)
            return;
        string href = e.ClickedElement.GetAttribute("href");
        // Custom routing instead of letting the OS open the link:
        MyAppRouter.Navigate(href);
    }

    private void OnEditorKeyDown(object sender, KeyEventArgs e)
    {
        if (e.KeyCode == Keys.Escape && htmlEditor1.EditorMode == EditorModes.ReadOnlyPreview)
        {
            htmlEditor1.EditorMode = EditorModes.WysiwygDesign;
            e.Handled = true;
        }
    }
}

Imports System
Imports System.Windows.Forms
Imports SpiceLogic.HtmlEditor.Abstractions
Imports SpiceLogic.HtmlEditor.WinForms
Imports SpiceLogic.HtmlEditor.WinForms.Models.BOs.EditorEventArgs

End Sub

Public Partial Class MainForm
    Inherits Form
    Public Sub New()
        InitializeComponent()
        htmlEditor1.EditorModeChanged += AddressOf OnEditorModeChanged
        htmlEditor1.HtmlElementClicked += AddressOf OnHtmlElementClicked
        htmlEditor1.KeyDown += AddressOf OnEditorKeyDown

The same code path covers all three recurring tickets: the editor flips to a true read-only render, the toolbar disappears, links are still clickable (routed through your app), and Escape returns the user to Design without losing the document.