rtf and break line

Hi all,
I m a beginner with developement and we work with asp net 2.0
i have a web page with some text box in this text box i type some string and type enter at the end of line as this ;
line 1
line 2
line 3
 
i must to generate a document rtf => ok that's ok but the problem IS it not possible for the moment to add the break line between ..
I've try to replace \r\n by \par (carriage return in rtf) but it s not possible ..
have you got any idea ?
text = ctrlText.Replace("\r\n", "\par"); => not compiling !

Thanks for your time and comment 
...