抛出表达式

C#7.0 允许在某些地方作为表达式投掷：

class Person
{
    public string Name { get; }

    public Person(string name) => Name = name ?? throw new ArgumentNullException(nameof(name));

    public string GetFirstName()
    {
        var parts = Name.Split(' ');
        return (parts.Length > 0) ? parts[0] : throw new InvalidOperationException("No name!");
    }

    public string GetLastName() => throw new NotImplementedException();
}

在 C#7.0 之前，如果要从表达式主体中抛出异常，则必须：

var spoons = "dinner,desert,soup".Split(',');

var spoonsArray = spoons.Length > 0 ? spoons : null;

if (spoonsArray == null) 
{
    throw new Exception("There are no spoons");
}

要么

var spoonsArray = spoons.Length > 0 
    ? spoons 
    : new Func<string[]>(() => 
      {
          throw new Exception("There are no spoons");
      })();

在 C#7.0 中，上面现在简化为：

var spoonsArray = spoons.Length > 0 ? spoons : throw new Exception("There are no spoons");