C# Cannot escape quotes in a regex string

Question

I am trying to match quotes using regex but I don't manage to escape them in the @string - I am getting an error:

output = Regex.Replace(str, @"[\d-']", string.Empty);    // valid

output = Regex.Replace(str, @"[\d-'\"]", string.Empty);  // not valid!

This one is also does not work:

string str = "[\d-'\"]" // bad compile constant value!

Answer 1

To escape a " in an a verbatim string, use "":

Regex.Replace(str, @"[\d-'""]", string.Empty);

Answer 2

The @ token suppresses \ escaping. If you remove the @ token it will work as expected, but you would have to escape the first backslash, i.e. "[\\d-'\"]"