How to: Extract the Text Content from a RichTextBox
This example shows how to extract the contents of a RichTextBox as plain text.
Example
The following Extensible Application Markup Language (XAML) code describes a named RichTextBox control with simple content.
<RichTextBox Name="richTB">
<FlowDocument>
<Paragraph>
<Run>Paragraph 1</Run>
</Paragraph>
<Paragraph>
<Run>Paragraph 2</Run>
</Paragraph>
<Paragraph>
<Run>Paragraph 3</Run>
</Paragraph>
</FlowDocument>
</RichTextBox>
The following code implements a method that takes a RichTextBox as an argument, and returns a string representing the plain text contents of the RichTextBox.
The method creates a new TextRange from the contents of the RichTextBox, using the ContentStart and ContentEnd to indicate the range of the contents to extract. ContentStart and ContentEnd properties each return a TextPointer, and are accessible on the underlying FlowDocument that represents the contents of the RichTextBox. TextRange provides a Text property, which returns the plain text portions of the TextRange as a string.
string StringFromRichTextBox(RichTextBox rtb)
{
TextRange textRange = new TextRange(
// TextPointer to the start of content in the RichTextBox.
rtb.Document.ContentStart,
// TextPointer to the end of content in the RichTextBox.
rtb.Document.ContentEnd
);
// The Text property on a TextRange object returns a string
// representing the plain text content of the TextRange.
return textRange.Text;
}