Use Regex.Replace to get the same value back

string output = Regex.Replace(input, pattern, replacement);

I get replacement patterns from a database to transform inputs into an expected format.

I need a replacement pattern that will return the same value as the input.

I tried (.) but that did not work.

What do I need?

Thanks,

Jon Jacobs
In transmission, subatomic particles managed by professionals.
No innocent electrons were harmed.