mjzammit 0 Newbie Poster

Hi
i am working on a project, ASP.NET Web Application and i want to highlight a number words which would have been found programatically from the textbox.
To find a string in the textbox i managed to do, my problem is to highlight the text found in the TextBox.
I tried using SelectionStart and SelectionLength but it is giving me an error, stating that a directive might be missing. They only seem to work for me if i am using a Windows application.
Is there a way of adding a windows applcation to my web application???
or even find the line number from the textbox of where the string is???
i am writing in c#