Learning C# 3.0

Chapter 7: Classes and Objects

Quiz Solutions

Solution to Question 7-1. A class defines a new type; an object is a single instance of that type.

Solution to Question 7-2. The keyword private indicates that access is limited to methods of the defining class.

Solution to Question 7-3. The keyword public indicates that access is available to methods in any class.

Solution to Question 7-4. When you create an instance of an object, the class’s constructor is called.

Solution to Question 7-5. A default constructor is a constructor that takes no parameters. If you do not create any constructor at all for your class, a default constructor is implicitly created.

Solution to Question 7-6. None. A constructor is not defined to return a type, and is not marked void.

Solution to Question 7-7. You can initialize the value of a member variable either in the constructor, using assignment, or when the member variable is created:

private int myVariable = 88;

Technically, only the latter is truly initialization; assigning it in the constructor is not as efficient.

Solution to Question 7-8. this refers to the object itself—the current instance of the class.

Solution to Question 7-9. A static method has no this reference. It does not belong to an instance; it belongs to the class and can call only other static methods.

You access a static method through the name of the class:

Dog myDog = new Dog(  );
myDog.InstanceMethod(  );
Dog.StaticMethod(  );

Of course, from within any method (including static methods), you can ...