Question

Dumb question.

Lets say I have a bunch of person objects with their fields all filled in with data and I have an employee type that derives from the person class and has extra fields related to being an employee. How do I get a employee object for a particular existing person object? i.e. How do I pass in the person object to the employee?

Answer 1

If the person was created as an employee, then just cast:

Person person = new Employee(); // for some reason ... Employee emp = (Employee)person; 

If the person is just a person: you can’t; you could have the employee encapsulate the Person – or you can copy the fields:

class Employee { // encapsulation   private readonly Person person;   public Person {get {return person;}}   public Employee(Person person) {this.person = person;}   public Employee() : this(new Person()) {} } 

or

class Employee : Person { // inheritance   public Employee(Person person) : base(person) {}   public Employee() {} } class Person {     public Person(Person template) {         this.Name = template.Name; // etc     }     public Person() {} }