c# - 如何将 IEnumerable 转换为 string[] 以便我可以将它与 String.Join 一起使用？

Question

如何转换 IEnumerable<char> “非字母”到 string[]以便我可以将它与 String.Join 一起使用？

string message = "This is a test message.";

var nonLetters = message.Where(x => !Char.IsLetter(x));

Console.WriteLine("There are {0} non-characters in \"{1}\" and they are: {2}", 
    nonLetters.Count(), 
    message,
    String.Join(", ", nonLetters.ToArray())
    );

Answer 1

string[] foo = nonLetters.Select(c => c.ToString()).ToArray();