WPF HTML Editor Control

WPF buyers notice when a third-party toolbar looks blurry beside the rest of the application. Every toolbar button in the 3.x line is a XAML vector path, not a PNG asset.

The icon set stays crisp at 100%, 125%, 150%, 175%, and 200% DPI, and on 4K monitors and per-monitor DPI configurations. That matters when your app runs on developer workstations, finance desktops, industrial terminals, and modern laptops with mixed scaling.

This is one of the practical differences between a WPF-focused control and a control merely hosted inside a WPF window. The toolbar can live visually inside your WPF application instead of looking like an older desktop component pasted on top.

Some WPF screens only need an HTML fragment saved into a database column. Other workflows need a complete document for email, export, preview, or integration with another system. The editor exposes both shapes without forcing you to scrape the document yourself.

• BodyHtml, the inner HTML of the document body, useful when you store content inside your own page, template, or database column.
• DocumentHtml, the full HTML document including wrapper, header, and DOCTYPE, useful when you save or send standalone HTML.

HTML5 is the default document type in 3.x, with override controls available for older render targets. That gives your WPF app a predictable output contract for templates, emails, CRM notes, and ERP letters.

Business users paste screenshots, insert logos, link product images, and expect the content to survive when it is emailed or published. The editor supports images from a local file, an absolute URL, or directly from the clipboard.

Clipboard images can be embedded as Base64 Data URIs so the HTML is self-contained, or saved to a base folder and referenced by relative path using the editor's BaseUrl. Pasted screenshots and photos auto-resize to a sensible maximum width by default, controlled by MaxPastedImageWidth.

When you need to publish, EmbedLocalImagesAsBase64() walks the document and converts every local image to a Base64 Data URI in a single call. YouTube embedding is supported through the toolbar, with the option to add ?rel=0. Hyperlinks support cross-document bookmark targets through the hyperlink dialog.

European enterprise WPF apps cannot treat localization as a cosmetic afterthought. Set one property and the editor UI reflows:

editor.Language = EditorLanguage.German;

Every toolbar tooltip, dialog caption, dialog button, and context-menu item appears in the chosen language. Fourteen UI languages are bundled: English (US), English (UK), German, Dutch, French, Spanish, Italian, Danish, Polish, Norwegian, Czech, Swedish, Portuguese (Brazil), and Portuguese (Portugal).

UI language and spell-check language are independent. You can run a German UI with an English spell-check dictionary if users edit English content in a German shell. UI language is set with Language, spell-check language is set with SpellCheckOption.SpellCheckLanguage.

An embedded editor should not fight the host application for keyboard shortcuts. In a mature WPF app, the keyboard already belongs to menus, ribbons, commands, and user muscle memory.

The KeyBindings manager exposes binding, unbinding, overriding, disabling, enabling, and querying for editor actions represented by EditorActionId. Thirty-five actions are covered: bold, italic, underline, cut, copy, paste, undo, redo, search, spell check, ordered and unordered list commands, alignment commands, insert commands for table, image, hyperlink, symbol, and YouTube video, font color, highlight color, indent, outdent, and more.

Use it to keep familiar shortcuts where users expect them, or to let your host application's global commands win when the editor has focus.

The editor uses standard WPF theming. Swap a single ResourceDictionary to retheme it for light mode, dark mode, or your own design system colors and typography. The XAML vector toolbar adapts to brushes you supply.

There is no proprietary skin engine to learn and no separate theme format to bolt on. It follows standard WPF resource resolution, the way you already style the rest of your application.

For teams that need to retemplate dialogs end to end or align deeply with a corporate WPF design system, the Source Code License includes the full source code of the control. That is why the WPF product speaks directly to buyers who expect customization, not just configuration.

Not every user who formats an email letter, support reply, or ERP document template should be asked to write CSS. The visual CSS style builder is available at design time through the WPF property surface and at runtime from the editor toolbar.

End users pick font, size, color, background, border, margin, and padding from familiar controls. The editor writes the equivalent inline or class-scoped CSS into the document.

To add your own pages to the style builder, for example a Corporate Branding tab with your standard color palette, implement IEditorStylePage and decorate the form with FormSelectorPageAttribute. That gives your application a supported extension point instead of a separate styling workaround.

Senior WPF developers need more than a toolbar. They need an API surface that can be driven from their own commands, bindings, save pipeline, and template workflow.

• Content service. Read, set, insert, transform, and export HTML through the Content service. Sub-services for MailMerge and TableAuthoringService.
• Caret service. Get and set caret position by point or by index through the Caret service.
• Editor commands. Cut, copy, paste, undo, redo, search, replace, print, and command execution through the Editor service.
• Formatting service. Apply bold, italic, underline, font, colors, alignment, lists, headings, and format removal through Formatting.
• Selection service. Read selected HTML, select text, select all, and trim selections through Selection.
• State query service. Ask whether the current selection is bold, italic, inside a table, undoable, or redoable, with 37 query methods through StateQuery.
• HTML-Changed event. HtmlChanged fires immediately when the document changes.
• Email-ready output. Content.GetEmailMessageWithLocalImagesEmbedded() returns a populated MailMessage with images embedded.
• Enter-key behavior. Choose paragraph (<p>) or line-break (<br>) behavior through EnterKeyResponse.