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copied!<p>Here is my modified code for recursively format text. It handles Bold, Italic, Underline and LineBreak but can easily be extended to support more (modify the <strong>switch</strong> statement).</p> <pre class="lang-cs prettyprint-override"><code>public static class MyBehavior { public static string GetFormattedText(DependencyObject obj) { return (string)obj.GetValue(FormattedTextProperty); } public static void SetFormattedText(DependencyObject obj, string value) { obj.SetValue(FormattedTextProperty, value); } public static readonly DependencyProperty FormattedTextProperty = DependencyProperty.RegisterAttached("FormattedText", typeof(string), typeof(MyBehavior), new UIPropertyMetadata("", FormattedTextChanged)); static Inline Traverse(string value) { // Get the sections/inlines string[] sections = SplitIntoSections(value); // Check for grouping if (sections.Length.Equals(1)) { string section = sections[0]; string token; // E.g <Bold> int tokenStart, tokenEnd; // Where the token/section starts and ends. // Check for token if (GetTokenInfo(section, out token, out tokenStart, out tokenEnd)) { // Get the content to further examination string content = token.Length.Equals(tokenEnd - tokenStart) ? null : section.Substring(token.Length, section.Length - 1 - token.Length * 2); switch (token) { case "<Bold>": return new Bold(Traverse(content)); case "<Italic>": return new Italic(Traverse(content)); case "<Underline>": return new Underline(Traverse(content)); case "<LineBreak/>": return new LineBreak(); default: return new Run(section); } } else return new Run(section); } else // Group together { Span span = new Span(); foreach (string section in sections) span.Inlines.Add(Traverse(section)); return span; } } /// <summary> /// Examines the passed string and find the first token, where it begins and where it ends. /// </summary> /// <param name="value">The string to examine.</param> /// <param name="token">The found token.</param> /// <param name="startIndex">Where the token begins.</param> /// <param name="endIndex">Where the end-token ends.</param> /// <returns>True if a token was found.</returns> static bool GetTokenInfo(string value, out string token, out int startIndex, out int endIndex) { token = null; endIndex = -1; startIndex = value.IndexOf("<"); int startTokenEndIndex = value.IndexOf(">"); // No token here if (startIndex < 0) return false; // No token here if (startTokenEndIndex < 0) return false; token = value.Substring(startIndex, startTokenEndIndex - startIndex + 1); // Check for closed token. E.g. <LineBreak/> if (token.EndsWith("/>")) { endIndex = startIndex + token.Length; return true; } string endToken = token.Insert(1, "/"); // Detect nesting; int nesting = 0; int temp_startTokenIndex = -1; int temp_endTokenIndex = -1; int pos = 0; do { temp_startTokenIndex = value.IndexOf(token, pos); temp_endTokenIndex = value.IndexOf(endToken, pos); if (temp_startTokenIndex >= 0 && temp_startTokenIndex < temp_endTokenIndex) { nesting++; pos = temp_startTokenIndex + token.Length; } else if (temp_endTokenIndex >= 0 && nesting > 0) { nesting--; pos = temp_endTokenIndex + endToken.Length; } else // Invalid tokenized string return false; } while (nesting > 0); endIndex = pos; return true; } /// <summary> /// Splits the string into sections of tokens and regular text. /// </summary> /// <param name="value">The string to split.</param> /// <returns>An array with the sections.</returns> static string[] SplitIntoSections(string value) { List<string> sections = new List<string>(); while (!string.IsNullOrEmpty(value)) { string token; int tokenStartIndex, tokenEndIndex; // Check if this is a token section if (GetTokenInfo(value, out token, out tokenStartIndex, out tokenEndIndex)) { // Add pretext if the token isn't from the start if (tokenStartIndex > 0) sections.Add(value.Substring(0, tokenStartIndex)); sections.Add(value.Substring(tokenStartIndex, tokenEndIndex - tokenStartIndex)); value = value.Substring(tokenEndIndex); // Trim away } else { // No tokens, just add the text sections.Add(value); value = null; } } return sections.ToArray(); } private static void FormattedTextChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e) { string value = e.NewValue as string; TextBlock textBlock = sender as TextBlock; if (textBlock != null) textBlock.Inlines.Add(Traverse(value)); } } </code></pre> <hr /> <p><b>Edit:</b> (proposed by Spook)</p> <p>A shorter version, but requires the text to be XML-valid:</p> <pre class="lang-cs prettyprint-override"><code>using System.Xml; // (...) public static class TextBlockHelper { #region FormattedText Attached dependency property public static string GetFormattedText(DependencyObject obj) { return (string)obj.GetValue(FormattedTextProperty); } public static void SetFormattedText(DependencyObject obj, string value) { obj.SetValue(FormattedTextProperty, value); } public static readonly DependencyProperty FormattedTextProperty = DependencyProperty.RegisterAttached("FormattedText", typeof(string), typeof(TextBlockHelper), new UIPropertyMetadata("", FormattedTextChanged)); private static void FormattedTextChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e) { string value = e.NewValue as string; TextBlock textBlock = sender as TextBlock; if (textBlock != null) { textBlock.Inlines.Clear(); textBlock.Inlines.Add(Process(value)); } } #endregion static Inline Process(string value) { XmlDocument doc = new XmlDocument(); doc.LoadXml(value); Span span = new Span(); InternalProcess(span, doc.ChildNodes[0]); return span; } private static void InternalProcess(Span span, XmlNode xmlNode) { foreach (XmlNode child in xmlNode) { if (child is XmlText) { span.Inlines.Add(new Run(child.InnerText)); } else if (child is XmlElement) { switch (child.Name.ToUpper()) { case "B": case "BOLD": { Span boldSpan = new Span(); InternalProcess(boldSpan, child); Bold bold = new Bold(boldSpan); span.Inlines.Add(bold); break; } case "I": case "ITALIC": { Span italicSpan = new Span(); InternalProcess(italicSpan, child); Italic italic = new Italic(italicSpan); span.Inlines.Add(italic); break; } case "U": case "UNDERLINE": { Span underlineSpan = new Span(); InternalProcess(underlineSpan, child); Underline underline = new Underline(underlineSpan); span.Inlines.Add(underline); break; } } } } } } </code></pre> <p>And an example of usage:</p> <pre><code><RootItem xmlns:u="clr-namespace:MyApp.Helpers"> <TextBlock u:TextBlockHelper.FormattedText="{Binding SomeProperty}" /> </RootItem> </code></pre>

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