C#: Removing common invalid characters from a string: improve this algorithm

Question

Consider the requirement to strip invalid characters from a string. The characters just need to be removed and replace with blank or string.Empty.

Answer 1

This is pretty clean. Restricts it to valid characters instead of removing invalid ones. You should split it to constants probably:

string clean = new string(@"Sour!ce Str&*(@ing".Where(c => 
@"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ ,.".Contains(c)).ToArray()