How do you remove repeated characters in a string

Question

I have a website which allows users to comment on photos. Of course, users leave comments like:

\'OMGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGG

Answer 1

var nonRepeatedChars = myString.ToCharArray().Distinct().Where(c => !char.IsWhiteSpace(c) || !myString.Contains(c)).ToString();