C# - short check for null

Question

How do I replace the following code

if (customer.Person!=null)
 Console.WriteLine(customer.Person.Name);

with something like this

Console.WriteLine(customer.Person.Name?? "unknown");

Answer 1

You can't, I'm afraid - there's nothing like Groovy's null-safe dereferencing operator :(

I suppose you could create a "null object" for Person - i.e. a real instance, but with all the properties null. Then you could use:

Console.WriteLine((customer.Person ?? Person.Null).Name ?? "Unknown");

... but that's pretty horrible. (It's also not checking for customer being null.)

Another option would be to write an extension method on Person:

public static string NameOrDefault(this Person person, string defaultName)
{
    return person == null ? defaultName : person.Name ?? defaultName;
}

Then:

Console.WriteLine(customer.Person.NameOrDefault("Unknown");