I was trying to validate a multipline asp text box that can have a maximum of 150 word characters but any number of white space, carriage returns or tabs and special characters. I tried several regex but all were failing when there was a carriage return(Newline / Enterkey ) on the multiline textbox.

Then I found this expression which validated the newlines in the multiline textbox:

"[\s\S]{0,150}" .

The basics!!  Try this out , this works!!