Verify Text in a Silverlight RichTextBox

PROBLEM

I cannot verify all the text or its properties in my Silverlight RichTextBox. The contents are either not visible or each word is contained in an individual TextBlock in the Visual Tree.

SOLUTION

The Silverlight RichTextBox is tricky to work with. It is a "container" type of control, meaning it contains other "block" elements, usually the Paragraph or Section. It is these block elements that hold the actual text displayed in the RichTextBox. Thus, to fetch the displayed text, you must enumerate through the individual blocks and fetch the text from each block element.

To make matters worse, the contents of the RichTextBox may not be contained in the Silverlight Visual Tree. You have to get the Xaml property and parse the contents yourself. Here is an example. Let's assume that you have this in the XAML file for your Silverlight application:

<RichTextBox AutomationProperties.AutomationId="richTextBox1" Name="richTextBox1" Margin="310,6,6,235">

<Paragraph FontSize="11" FontFamily="Portable User Interface" Foreground="#FF000000" FontWeight="Normal" FontStyle="Normal" FontStretch="Normal" TextAlignment="Left">

<Run FontWeight="Bold" Text="Now is the time for all good men to come to the aid of their country." />

</Paragraph>

</RichTextBox>

The application will show text as shown below.

However in DOM Explorer all you see is this:

<?xml version="1.0"?>

<richtextbox Name="richTextBox1" AutomationId="richTextBox1" Uid="16157963">

<grid Name="RootElement" Uid="37840511">

<border Name="Border" Uid="34030663">

<border Name="MouseOverBorder" Uid="33607346">

<scrollviewer Name="ContentElement" AutomationId="ContentElement" Uid="63386473">

<border Uid="54749715">

<grid Uid="35909463">

<scrollcontentpresenter Name="ScrollContentPresenter" Uid="5020285">

<richtextboxview BaseType="RichTextBoxView" Uid="22985394" />

</scrollcontentpresenter>

<rectangle Uid="26673201" />

<scrollbar Name="VerticalScrollBar" AutomationId="VerticalScrollBar" Uid="45182569" />

<scrollbar Name="HorizontalScrollBar" AutomationId="HorizontalScrollBar" Uid="3989940" />

</grid>

</border>

</scrollviewer>

</border>

<border Name="DisabledVisualElement" Uid="38732217" />

<border Name="FocusVisualElement" Uid="13045638" />

</grid>

</richtextbox>

Notice that there's no text in the DOM view, even though it is specified in the XAML and displayed in the application. We have to use code to fetch the XAML that the RichTextBox holds as data, then parse out the text buried in it. Here's an example:

C#

// Fetch the XAML property of the RichTextBox

string rtbContents = (string)Pages.SilverlightAppTesting.SilverlightApp.RichTextBox1Richtextbox.GetProperty(new AutomationProperty("Xaml", typeof(string)));

// Load it into an XmlDocument for easier parsing

XmlDocument doc = new System.Xml.XmlDocument();

doc.LoadXml(rtbContents);

// Find all "Run" nodes as this is where the text is buried

XmlNodeList runNodes = doc.GetElementsByTagName("Run");

// Display the Text attribute of each run node

foreach(XmlNode runNode in runNodes)

{

Log.WriteLine(runNode.Attributes["Text"].Value);

}

Visual Basic

' Fetch the XAML property of the RichTextBox

Dim rtbContents As String = DirectCast(Pages.SilverlightAppTesting.SilverlightApp.RichTextBox1Richtextbox.GetProperty(New AutomationProperty("Xaml", GetType(String))), String)

' Load it into an XmlDocument for easier parsing

Dim doc As XmlDocument = New System.Xml.XmlDocument()

doc.LoadXml(rtbContents)

' Find all "Run" nodes as this is where the text is buried

Dim runNodes As XmlNodeList = doc.GetElementsByTagName("Run")

' Display the Text attribute of each run node

For Each runNode As XmlNode In runNodes

Log.WriteLine(runNode.Attributes("Text").Value)

Next

Here's how to verify the text is bold:

C#

string rtbContents = (string)Pages.SilverlightAppTesting.SilverlightApp.RichTextBox1Richtextbox.GetProperty(new AutomationProperty("Xaml", typeof(string)));

Log.WriteLine(rtbContents);

// Load the RTB contents into an XElement for parsing

XElement xElem = XElement.Parse(rtbContents);

// Find the <Run node.

XElement runElem = xElem.Descendants().First((e) => "Run".Equals(e.Name.LocalName));

// Fetch the FontWeight attribute

XAttribute attr = runElem.Attribute("FontWeight");

Log.WriteLine(attr.Value);

// Verify it is Bold

Assert.AreEqual<string>("Bold", attr.Value);

Visual Basic

Dim rtbContents As String = DirectCast(Pages.SilverlightAppTesting.SilverlightApp.RichTextBox1Richtextbox.GetProperty(New AutomationProperty("Xaml", GetType(String))), String)

Log.WriteLine(rtbContents)

' Load the RTB contents into an XElement for parsing

Dim xElem As XElement = XElement.Parse(rtbContents)

' Find the <Run node.

Dim runElem As XElement = xElem.Descendants().First(Function(e) "Run".Equals(e.Name.LocalName))

' Fetch the FontWeight attribute

Dim attr As XAttribute = runElem.Attribute("FontWeight")

Log.WriteLine(attr.Value)

' Verify it is Bold

Assert.AreEqual(Of String)("Bold", attr.Value)