Usage:

1. Add a System.Xml.Linq reference to your project

2. Download the source and copy the following files in the Control folder to your project:

* ucXmlRichTextBox.cs
* ucXmlRichTextBox.Designer.cs
* ucXmlRichTextBox.resx
* XmlStateMachine.cs

3. Open your Windows form in design view and drag and drop the "ucXmlRichTextBox" from the Toolbox to your form.

4. In the code behind, set the "Xml" property of the ucXmlRichTextBox to some valid XML:

ucXmlRichTextBox1.Xml = myValidXml;

5. You're done.

NOTE: You can clear the text by setting the Text property to String.Empty or anything else you want.