Regex to remove all special characters from string?

Question

I\'m completely incapable of regular expressions, and so I need some help with a problem that I think would best be solved by using regular expressions.

I have list

Answer 1

It really depends on your definition of special characters. I find that a whitelist rather than a blacklist is the best approach in most situations:

tmp = Regex.Replace(n, "[^0-9a-zA-Z]+", "");

You should be careful with your current approach because the following two items will be converted to the same string and will therefore be indistinguishable:

"TRA-12:123"
"TRA-121:23"

Answer 2

tmp = Regex.Replace(n, @"\W+", "");

\w matches letters, digits, and underscores, \W is the negated version.

Answer 3

You can use:

string regExp = "\\W";

This is equivalent to Daniel's "[^a-zA-Z0-9]"

\W matches any nonword character. Equivalent to the Unicode categories [^\p{Ll}\p{Lu}\p{Lt}\p{Lo}\p{Nd}\p{Pc}].