Removing all whitespace lines from a multi-line string efficiently

Question

In C# what\'s the best way to remove blank lines i.e., lines that contain only whitespace from a string? I\'m happy to use a Regex if that\'s the best solution.

EDIT

Answer 1

off the top of my head...

string fixed = Regex.Replace(input, "\s*(\n)","$1");

turns this:

fdasdf
asdf
[tabs]

[spaces]  

asdf

into this:

fdasdf
asdf
asdf