I need to use an Enum for readability and as Type string.

Question

I have this Enum that I am using along with an extension method. And I was just wondering if I should be able to assign an Error Level to a string variable like so..... string id = ErrorLevel.Low. For some reason I am getting a compile error... A value of type 'ErrorLevelExtensions.ErrorLevel' cannot be used as a default parameter because there are no standard conversions to type string. I thought my extension method returns a string?!?

public enum ErrorLevel
{
  None,
  Low,
  High,
  SoylentGreen
}

public static class ErrorLevelExtensions
{
  public static string ToFriendlyString(this ErrorLevel me)
  {
    switch(me)
    {
      case ErrorLevel.None:
        return "Everything is OK";
      case ErrorLevel.Low:
        return "SNAFU, if you know what I mean.";
      case ErrorLevel.High:
        return "Reaching TARFU levels";
      case ErrorLevel.SoylentGreen:
        return "ITS PEOPLE!!!!";
      default:
        return "Everything is Fine";
    }
  }
}

Answer 1

An extension method is just a method that you can call on a type, not a method that does an implicit conversion to another type.

You can call it explicitly though:

string id = ErrorLevel.Low.ToFriendlyString();