Remove all "invisible" chars from a string?

Question

I'm writing a little class to read a list of key value pairs from a file and write to a Dictionary<string, string>. This file will have this format:

key1:value1
key2:value2
key3:value3
...

This should be pretty easy to do, but since a user is going to edit this file manually, how should I deal with whitespaces, tabs, extra line jumps and stuff like that? I can probably use Replace to remove whitespaces and tabs, but, is there any other "invisible" characters I'm missing?

Or maybe I can remove all characters that are not alphanumeric, ":" and line jumps (since line jumps are what separate one pair from another), and then remove all extra line jumps. If this, I don't know how to remove "all-except-some" characters.

Of course I can also check for errors like "key1:value1:somethingelse". But stuff like that doesn't really matter much because it's obviously the user's fault and I would just show a "Invalid format" message. I just want to deal with the basic stuff and then put all that in a try/catch block just in case anything else goes wrong.

Note: I do NOT need any whitespaces at all, even inside a key or a value.

Answer 1

I did this one recently when I finally got pissed off at too much undocumented garbage forming bad xml was coming through in a feed. It effectively trims off anything that doesn't fall between a space and the ~ in the ASCII table:

static public string StripControlChars(this string s)
{
    return Regex.Replace(s, @"[^\x20-\x7F]", "");
}

Combined with the other RegEx examples already posted it should get you where you want to go.

Answer 2

If you use Regex (Regular Expressions) you can filter out all of that with one function.

string newVariable Regex.Replace(variable, @"\s", "");

That will remove whitespace, invisible chars, \n, and \r.