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// Classes are always reference types.

class PointRef

{

// Same members as the Point structure.

// Be sure to change your constructor name to PointRef!

public PointRef(int XPos, int YPos)

{

X = XPos;

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Y = YPos;

}

}

Now, make use of your PointRef type within the following new method (note the code is identi-

cal to the ValueTypeAssignment() method). Assuming you have called this new method within

Main(), your output should look like that in Figure 4-11.

static void ReferenceTypeAssignment()

{

Console.WriteLine("Assigning reference types\n");

PointRef p1 = new PointRef(10, 10);

PointRef p2 = p1;

// Print both point refs.

p1.Display();

p2.Display();

// Change p1.X and print again.

p1.X = 100;

Console.WriteLine("\n=> Changed p1.X\n");

p1.Display();

p2.Display();

}

Figure 4-11.

Assignment of reference types copies the reference.

In this case, you have two references pointing to the same object on the managed heap. There-

fore, when you change the value of X using the p2 reference, p1.X reports the same value.