If you are using
System.Windows.Forms
, the perfect component (instead of using rich text box directly) is this HTML renderer offered in this CodeProject article:
A Professional HTML Renderer You Will Use[
^].
This approach is really good. The author introduces special URI scheme so you can use embedded resources of any kind, such as images, etc.
For WPF, you probably can use another one, but I did not test it:
WPF HTML Supported TextBlock[
^].
—SA