The document will immediately appear in the RTB. So, when an app loads a new document for display in the UI, it need only place that document in a view model property. Updates coming from the view model update the RTB automatically.How does the control minimize the processing load associated with data-binding a rich text document? It does it by handling updates differently, depending on the direction of an update: Since the Document property is a dependency property, the FS RTB can be data-bound to a view model, as is done in the demo app. The control adds both a formatting toolbar and a Document dependency property to the WPF RTB. The FS RTB control is designed to make it easy to use an RTB in a data-bound view, while minimizing the processing load that comes with processing data-bound rich text. Another understandable reason for making the RTB’s Document property non-bindable. If the control is bound to a database, typing a character in the RTB could trigger a round trip to a database. As a result, a data-bound RTB would be constantly updating the bindings, moving a large amount of formatted text as it does so. That means whenever a character is typed. Any data bindings on the text should be updated whenever the text changes. One has to assume a rich text document can grow quite large. In that context, the lack of data binding is understandable.Īnother reason to omit data binding from the control’s design has to do with processing load. Instead, I suspect its designers intended it to be used more like a word processor, whose documents are loaded and saved to separate files. Now, I haven't seen anything from Microsoft’s WPF team, so the following is a bit speculative, but here is why I think the property isn't bindable: Like the WinForms RichTextBox, the WPF RichTextBox isn't really designed to be bound to a database. I have seen several explanations on the Web as to why the Document property isn't bindable. As I noted above, this makes the control more difficult to use with the MVVM pattern, which has become the standard design pattern for WPF applications. Unfortunately, this property is not a dependency property, which means that WPF won't data-bind to the property. The WPF RTB control outputs its content in its Document property. Why the WPF RichTextBox Behaves as It Does If there is demand for a WPF 3.5 version, I'll consider backporting. The source code is provided in WPF 4.0 format I have dropped the WPF 3.5 version.These two buttons can be hidden by setting the CodeControlsVisibility visibility property to Visibility.Collapsed. Version 1.2 adds two new text-deiting buttons, 'Format as code block', and 'Format as inline code'.Version 1.1 did not implement this visual behavior Version 1.2 does. The text alignment buttons should be treated as a single-select button group-when one button is selected, the previously-selected button should be deselected.The List Numbering and List Bulleting buttons have been made toggle buttons and have been grouped together. The current version of the control is Version 1.2 it incorporates the following changes from Version 1.1: Both solutions are included in the zip file at the top of this article. It is included, along with a demo app, as both Visual Studio 2008 and Visual Studio 2010 RC solutions. The control provided in this article does exactly that. Even so, they are inconveniences, and it would be nice to have a version of the control that eliminates all of these problems. It doesn't have a built-in formatting toolbar, which means additional work to set up the control in a host application.Īs it turns out, the first two characteristics were not oversights, and they probably make a lot of sense.It outputs its content as a WPF FlowDocument, rather than as an XAML markup string.It doesn't data-bind well, which makes it harder to use with the MVVM pattern and.WPF’s RichTextBox (RTB) is very good, but it suffers from several shortcomings:
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