Task 1: Explore the Employer Class

Open the Employer file in Visual Studio and examine the code. In addition to the three members—nextId, Id, and Value—the class includes some methods like ToString() and Equals().

You can refer to these examples as you fill in the missing pieces in the other classes, but for now let’s take a closer look at the constructors.

Assign a Unique ID

One neat trick we can use is to automatically assign each new object a unique ID number.

Examine the two constructors in Employer.cs:

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public class Employer {
   public int Id { get; }
   private static int nextId = 1;
   public string Value { get; set; }

   public Employer ()
   {
      Id = nextId;
      nextId++;
   }

   public Employer (string value) : this()
   {
      Value = value;
   }

   // Additional methods omitted from this code block

1. Line 3 declares the field nextId. Since it is static, its changing value is NOT stored within any Employer object.

2. The first constructor (lines 6 - 10) accepts no arguments and assigns the value of nextId to the id field. It then increments nextId. Thus, every new Employer object will get a different ID number.

3. The second constructor (lines 12 - 15) assigns the value field. It ALSO initializes id for the object by calling the first constructor statement with the :this() syntax. Including :this() in any Employer constructor makes initializing id a default behavior.

On to Task 2 .