// instance methods can use a static method, a static method cannot use an instance method
private static void Report(Mary child, string state)
{
var stateValue = typeof(Mary).GetField($"_{state}").GetValue(child);
Console.WriteLine($"{child._name}'s {state} is now {stateValue}");
Console.WriteLine();
}
public static void Teach(Mary child)
{
Action("teaches", child);
child._iq += 20;
Report(child, "iq");
}
public static void PlayWith(Mary child)
{
Action("plays with", child);
child._happiness += 20;
Report(child, "happiness");
}
// static methods
public static void Feed(Mary child)
{
Action("feeds", child);
child._fullness += 20;
Report(child, "fullness");
}
// private helper methods.
private static void Action(string action, Mary child) => Console.WriteLine($"Mary {action} {child._name}");
