![]() Shows us that we can stuff pretty much whatever we want to into the Header property instead of just a string and then have the TreeView render it - a greatĮxample of why it's so easy to customize the look of WPF controls. As you can see, I can just specify a text string and then have it rendered directly withoutĭoing anything else, but this is WPF being nice to us - internally, it wraps the text inside of a TextBlock control, instead of forcing you to do it. The Header is an interesting property, though. TreeViewItem's with images and other controls ![]() By default, a TreeViewItem is not expanded, but to show you the structure of the example, I have used the IsExpanded property to expand the two parent items. To specify the text we want displayed for each node, we use the Header property. The TreeView control and its child objects are also child tags to its parent object. We simply declare the TreeViewItem objects directly in the XAML, in the same structure that we want to display them in, where the first tag is a child of This is indeed very easy to get started with, as you can see from the example here: If you are looking for full editing functionality including adding, removing and renaming nodes, you may want to switch to a "Model-View-ViewModel" methodology in which the JToken hierarchy becomes the model and a lightweight view model handles modifications and notifications.The TreeView control: A simple TreeView exampleĪs we talked about in the previous article, the WPF TreeView can be used in a very simple manner, by adding TreeViewItem objects to it, either fromĬode-behind or simply by declaring them directly in your XAML. This approach binds the JSON to the tree directly. However, this should give you an idea of how to do the binding. by placing the value for JProperty tokens with only a single JValue child on the same row. Of course, the user interface could be made more beautiful, e.g. Then, when your user selects JSON data to view, you can do: var token = JToken.Parse(jsonString) Having done this, an extremely simple XAML markup that can display this hierarchy in a tree is: Throw new NotSupportedException(GetType().Name + " can only be used for one way conversion.") Public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture) Return methodInfo.Invoke(value, new object) Var methodInfo = value.GetType().GetMethod(methodName, new Type) Public object Convert(object value, Type targetType, object parameter, CultureInfo culture) Public sealed class MethodToValueConverter : IValueConverter In order to bind a hierarchy of these classes into a tree, you first need a converter to convert the JToken.Children() method into a property: // Respectfully adapted from ![]() The concrete Json.NET JToken classes for which templates are required are: This hierarchy can be bound into a WPF TreeView control using DataTemplate and HierarchicalDataTemplate to format data from all possible subclasses of JToken and iterate through their children. Json.NET has a static method JToken.Parse() (which is similar in purpose to XDocument.Parse()) and can turn a valid JSON string into a hierarchy of objects. You can do this with the Json.NET framework.
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