WPF Generate TextBlock Inlines
An old question, but I find accepted answer an absolute overkill. You don't need to parse the formatted text at all! Just wrap it up in Span element and you are done.
public class Attached{ public static readonly DependencyProperty FormattedTextProperty = DependencyProperty.RegisterAttached( "FormattedText", typeof(string), typeof(Attached), new FrameworkPropertyMetadata(string.Empty, FrameworkPropertyMetadataOptions.AffectsMeasure, FormattedTextPropertyChanged)); public static void SetFormattedText(DependencyObject textBlock, string value) { textBlock.SetValue(FormattedTextProperty, value); } public static string GetFormattedText(DependencyObject textBlock) { return (string)textBlock.GetValue(FormattedTextProperty); } private static void FormattedTextPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e) { var textBlock = d as TextBlock; if (textBlock == null) { return; } var formattedText = (string)e.NewValue ?? string.Empty; formattedText = string.Format("<Span xml:space=\"preserve\" xmlns=\"http://schemas.microsoft.com/winfx/2006/xaml/presentation\">{0}</Span>", formattedText); textBlock.Inlines.Clear(); using (var xmlReader = XmlReader.Create(new StringReader(formattedText))) { var result = (Span)XamlReader.Load(xmlReader); textBlock.Inlines.Add(result); } }}Now you can use the FormattedText attached property either in your code:
string inlineExpression = "<Run Style=\"Theme.GrayText\">Once I saw a little bird, go hop, hop, hop.</Run>";Attached.SetFormattedText(myTextBlock1, inlineExpression);More importantly, straight from the XAML:
<TextBlock ns:Attached.FormattedText="{Binding Content}" />Where ns is the namespace you defined the Attached class in.
Recently i came across the same problem. So i decided to implement an attached property for TextBlock which takes a value of string type and then populates the Inlines collection on the fly. You can simply set the property value to something like this:
string inlineExpression = "Once i saw a little <bold>bird</bold>, <span>go <bold>hop, hop, hop</bold></span>.";InlineExpression.SetInlineExpression(myTextBlock1, inlineExpression);The styles are also supported:
string inlineExpression = "<run style="Theme.GrayText">Once i saw a little bird, go hop, hop, hop.</run>";InlineExpression.SetInlineExpression(myTextBlock1, inlineExpression);You can also use this attached property in XAML in a standard way.
Here is the code of the class which exposes this property:
public class InlineExpression{ public static readonly DependencyProperty InlineExpressionProperty = DependencyProperty.RegisterAttached( "InlineExpression", typeof(string), typeof(TextBlock), new FrameworkPropertyMetadata(string.Empty, FrameworkPropertyMetadataOptions.AffectsMeasure)); public static void SetInlineExpression(TextBlock textBlock, string value) { textBlock.SetValue(InlineExpressionProperty, value); textBlock.Inlines.Clear(); if (string.IsNullOrEmpty(value)) return; var descriptions = GetInlineDescriptions(value); if (descriptions.Length == 0) return; var inlines = GetInlines(textBlock, descriptions); if (inlines.Length == 0) return; textBlock.Inlines.AddRange(inlines); } public static string GetInlineExpression(TextBlock textBlock) { return (string)textBlock.GetValue(InlineExpressionProperty); } enum InlineType { Run, LineBreak, Span, Bold, Italic, Hyperlink, Underline } class InlineDescription { public InlineType Type { get; set; } public string Text { get; set; } public InlineDescription[] Inlines { get; set; } public string StyleName { get; set; } } private static Inline[] GetInlines(FrameworkElement element, IEnumerable<InlineDescription> inlineDescriptions) { var inlines = new List<Inline>(); foreach (var description in inlineDescriptions) { var inline = GetInline(element, description); if (inline != null) inlines.Add(inline); } return inlines.ToArray(); } private static Inline GetInline(FrameworkElement element, InlineDescription description) { Style style = null; if (!string.IsNullOrEmpty(description.StyleName)) { style = element.FindResource(description.StyleName) as Style; if (style == null) throw new InvalidOperationException("The style '" + description.StyleName + "' cannot be found"); } Inline inline = null; switch (description.Type) { case InlineType.Run: var run = new Run(description.Text); inline = run; break; case InlineType.LineBreak: var lineBreak = new LineBreak(); inline = lineBreak; break; case InlineType.Span: var span = new Span(); inline = span; break; case InlineType.Bold: var bold = new Bold(); inline = bold; break; case InlineType.Italic: var italic = new Italic(); inline = italic; break; case InlineType.Hyperlink: var hyperlink = new Hyperlink(); inline = hyperlink; break; case InlineType.Underline: var underline = new Underline(); inline = underline; break; } if (inline != null) { var span = inline as Span; if (span != null) { var childInlines = new List<Inline>(); foreach (var inlineDescription in description.Inlines) { var childInline = GetInline(element, inlineDescription); if (childInline == null) continue; childInlines.Add(childInline); } span.Inlines.AddRange(childInlines); } if (style != null) inline.Style = style; } return inline; } private static InlineDescription[] GetInlineDescriptions(string inlineExpression) { if (inlineExpression == null) return new InlineDescription[0]; inlineExpression = inlineExpression.Trim(); if (inlineExpression.Length == 0) return new InlineDescription[0]; inlineExpression = inlineExpression.Insert(0, @"<root>"); inlineExpression = inlineExpression.Insert(inlineExpression.Length, @"</root>"); var xmlTextReader = new XmlTextReader(new StringReader(inlineExpression)); var xmlDocument = new XmlDocument(); xmlDocument.Load(xmlTextReader); var rootElement = xmlDocument.DocumentElement; if (rootElement == null) return new InlineDescription[0]; var inlineDescriptions = new List<InlineDescription>(); foreach (XmlNode childNode in rootElement.ChildNodes) { var description = GetInlineDescription(childNode); if (description == null) continue; inlineDescriptions.Add(description); } return inlineDescriptions.ToArray(); } private static InlineDescription GetInlineDescription(XmlNode node) { var element = node as XmlElement; if (element != null) return GetInlineDescription(element); var text = node as XmlText; if (text != null) return GetInlineDescription(text); return null; } private static InlineDescription GetInlineDescription(XmlElement element) { InlineType type; var elementName = element.Name.ToLower(); switch (elementName) { case "run": type = InlineType.Run; break; case "linebreak": type = InlineType.LineBreak; break; case "span": type = InlineType.Span; break; case "bold": type = InlineType.Bold; break; case "italic": type = InlineType.Italic; break; case "hyperlink": type = InlineType.Hyperlink; break; case "underline": type = InlineType.Underline; break; default: return null; } string styleName = null; var attribute = element.GetAttributeNode("style"); if (attribute != null) styleName = attribute.Value; string text = null; var childDescriptions = new List<InlineDescription>(); if (type == InlineType.Run || type == InlineType.LineBreak) { text = element.InnerText; } else { foreach (XmlNode childNode in element.ChildNodes) { var childDescription = GetInlineDescription(childNode); if (childDescription == null) continue; childDescriptions.Add(childDescription); } } var inlineDescription = new InlineDescription { Type = type, StyleName = styleName, Text = text, Inlines = childDescriptions.ToArray() }; return inlineDescription; } private static InlineDescription GetInlineDescription(XmlText text) { var value = text.Value; if (string.IsNullOrEmpty(value)) return null; var inlineDescription = new InlineDescription { Type = InlineType.Run, Text = value }; return inlineDescription; }}
In XAML you could do something like this:
<GridViewColumn> <GridViewColumn.CellTemplate> <DataTemplate> <TextBlock> <Hyperlink NavigateUri="{Binding AUri}"> <Run Text="{Binding A}"/> </Hyperlink> <Run Text=" is doing "/> <Hyperlink NavigateUri="{Binding BUri}"> <Run Text="{Binding B}"/> </Hyperlink> </TextBlock> </DataTemplate> </GridViewColumn.CellTemplate></GridViewColumn>In code behind the same thing can be done but i would not recommend it since it involves using FrameworkElementFactories.