How to use named groups when performing a Regex.Replace()

Instead of "$2 $1", you can use "${secondMatch} ${firstMatch}".

There is a list of all the replacements you can do here.

Here is an abbreviated list:

$number – The captured group by number.

${name} – The captured group by name.

$$ – $ literal.

$& – Entire match.

$` – The input string before the match.

$’ – The input string after the match.

$+ – The last group captured.

$_ – The entire input string.