C# Reference type assignment VS value type assignment

Question

I understand the theoretical concept that assigning one reference type variable to another, only the reference is copied, not the object. assigning one value type variable to another, the object is copied. But I cannot spot the different in the code. would someone kindly point out the difference between the following two code blocks? Thank you!

REFERENCE TYPE ASSIGNMENT

using System;

class Employee
{
    private string m_name;

    public string Name
    {
        get { return m_name; }
        set { m_name = value; }
    }
}

class Program
{
    static void Main()
    {
        Employee joe = new Employee();
        joe.Name = "Joe";

        Employee bob = new Employee();
        bob.Name = "Bob";

        Console.WriteLine("Original Employee Values:");
        Console.WriteLine("joe = " + joe.Name);
        Console.WriteLine("bob = " + bob.Name);

        // assign joe reference to bob variable
        bob = joe;

        Console.WriteLine();
        Console.WriteLine("Values After Reference Assignment:");
        Console.WriteLine("joe = " + joe.Name);
        Console.WriteLine("bob = " + bob.Name);

        joe.Name = "Bobbi Jo";

        Console.WriteLine();
        Console.WriteLine("Values After Changing One Instance:");
        Console.WriteLine("joe = " + joe.Name);
        Console.WriteLine("bob = " + bob.Name);

        Console.ReadKey();
    }
}

VALUE TYPE ASSIGNMENT

using System;

struct Height
{
    private int m_inches;

    public int Inches
    {
        get { return m_inches; }
        set { m_inches = value; }
    }
}

class Program
{
    static void Main()
    {
        Height joe = new Height();
        joe.Inches = 71;

        Height bob = new Height();
        bob.Inches = 59;

        Console.WriteLine("Original Height
            Values:");
        Console.WriteLine("joe = " + joe.Inches);
        Console.WriteLine("bob = " + bob.Inches);

        // assign joe reference to bob variable
        bob = joe;

        Console.WriteLine();
        Console.WriteLine("Values After Value Assignment:");
        Console.WriteLine("joe = " + joe.Inches);
        Console.WriteLine("bob = " + bob.Inches);

        joe.Inches = 65;

        Console.WriteLine();
        Console.WriteLine("Values After Changing One Instance:");
        Console.WriteLine("joe = " + joe.Inches);
        Console.WriteLine("bob = " + bob.Inches);

        Console.ReadKey();
    }
}

Answer 1

Well, the obvious difference is that with the class example, it appears both joe and bob changed in the last part there, to the same value.

In the struct example, they keep their separate values, simply because each variable is a whole struct value by itself, not just a reference to a common object in memory somewhere.

The main code-wise difference being the type you use, class or struct, this dictates whether you're creating a reference type or a value type.