Basically, I have a RichTextBox and I want to convert the formatted contents of it to HTML so it can be sent as an email.

The method I am currently using does not give any formatting at all:

string message = new TextRange(messageTextBox.Document.ContentStart,
                               messageTextBox.Document.ContentEnd).Text;

So I searched around and found this, however, it is over 5 years old and in the comments an MSFT user has commented saying that it is no longer supported - "This sample has been removed from our sample set and is no longer supported", and the HTML it generates is in an older format than modern HTML or XHTML which would be better to have.

Can anybody show me how I can convert the formatted contents of a RichTextBox to HTML?

(So when the email is sent it the recipient sees the email with formatting)

c# wpf richtextbox flowdocument
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