cs11dotnet7/vscode/Chapter06/NullHandling/Program.cs
2022-02-27 19:08:52 +00:00

30 lines
727 B
C#

int thisCannotBeNull = 4;
//thisCannotBeNull = null; // compile error!
WriteLine(thisCannotBeNull);
int? thisCouldBeNull = null;
WriteLine(thisCouldBeNull);
WriteLine(thisCouldBeNull.GetValueOrDefault());
thisCouldBeNull = 7;
WriteLine(thisCouldBeNull);
WriteLine(thisCouldBeNull.GetValueOrDefault());
// the actual type of int? is Nullable<int>
Nullable<int> thisCouldAlsoBeNull = null;
thisCouldAlsoBeNull = 9;
WriteLine(thisCouldAlsoBeNull);
// Declaring non-nullable variables and parameters
Address address = new();
address.Building = null;
address.Street = null!; // null-forgiving operator
address.City = "London";
address.Region = "UK";
WriteLine(address.Building?.Length);
WriteLine(address.Street.Length);