If you meant to highlight some of the letters in a GridViewCell
when you type in some kind of a search box, you can check Highlighting Inline Search for RadGridView for Silverlight
blog post. However, if this is not your case could you please provide us with more detailed information about what you are trying to achieve?
We are looking forward to your reply.
Check out Telerik Analytics, the service which allows developers to discover app usage patterns, analyze user data, log exceptions, solve problems and profile application performance at run time. Watch the videos
and start improving your app based on facts, not hunches.