Deck 9: Object-Oriented Programming: Classes and Objects

Question 1

A ReadOnly property provides only a __________ accessor.

A)Set
B)Read
C)Get
D)Const

Answer 1

C

Question 2

A constructor call is required for every object that's created.

Answer 2

True

Question 3

Private class members are accessible only from outside the class in which they're declared.

Answer 3

False

Question 4

A(n)___________ is a special type of method that is used only when an object is created to initialize an object's data.

A)initializer
B)builder
C)constructor
D)definer

Question 5

A class can be used to create an instance of the class called a(n)________.

A)child
B)part
C)offspring
D)object

Question 6

Which of the following is a built-in reference type?

A)Integer
B)String
C)Boolean
D)Char

Question 7

A Throw statement immediately returns its __________ argument to the caller.

A)class
B)exception
C)object
D)method

Question 8

Visual Basic is known as a(n)__________ language because you can declare new class types as needed.

A)modifiable
B)growable
C)extensible
D)high-level

Question 9

Instance variables declared with Dim default to __________ access.

A)Private
B)Public
C)Class
D)Member

Question 10

How many classes are there in a program/app?

A)0
B)1
C)more than 1
D)The number of classes may vary.

Question 11

The compiler provides a default constructor with __________ parameter(s)in any class that does not explicitly declare a constructor.

A)0
B)1
C)2
D)any number of

Question 12

Object orientation uses classes primarily to:

A)develop algorithms
B)house data (attributes)and methods
C)organize large amounts of data
D)None of the above.

Question 13

A car has many __________,such as its color,the number of doors,the amount of gas in its tank,its current speed and its odometer reading.

A)methods
B)messages
C)attributes
D)clients

Question 14

You can provide a parameterless constructor that contains code and takes no parameters,or that takes only Optional parameters so you can call it with no arguments.

A)Required
B)Optional
C)Voluntary
D)Class

Question 15

Public class members are accessible wherever the program has a reference to an object of the class.

Question 16

What is the default value of a reference?

A)0
B)Nil
C)Nothing
D)Null

Question 17

An object-creation expression creates a new object of the class specified to the right of New and calls the object's constructor.

Question 18

Constructors cannot be overloaded.

Question 19

Each class you create becomes a new type that can be used to declare variables and create objects.

Question 20

A variable of a reference type contains:

A)information about the type and its data
B)data of that type
C)the address of the location in memory where data is stored
D)None of the above.

Question 21

Which statements successfully swap the contents of an array at index 3 and index 4?

A) values( 3 )= values( 4 )
Values( 4 )= values( 3 )
B) values( 4 )= values( 3 )
Values( 3 )= values( 4 )
C) Dim temp As Integer = values( 3 )
Values( 3 )= values( 4 )
Values( 4 )= temp;
D) Dim temp As Integer = values( 3 )
Values( 3 )= values( 4 )
Values( 4 )= values( 3 )

Question 22

Primitive-type variables refer to objects in a Visual Basic app.

Question 23

If a variable is said to have block scope then that variable:

A)can be accessed by all methods
B)can be accessed only by certain methods
C)can be accessed only by the method in which it was defined
D)None of the above

Question 24

Constructors are implemented as Sub methods because they cannot return values.

Question 25

A constructor method is invoked each time an object of the class is instantiated.

Question 26

Variables declared within class methods are called instance variables.

Question 27

Which function is called when another class's object is used where a String should be?

A)TranslateToString
B)String
C)ConvertToString
D)ToString

Question 28

Value types normally represent single pieces of data.

Question 29

A primitive-type variable can store exactly one value at a time,whereas one object can contain many individual pieces of data.

Question 30

Within a class's scope,class members are immediately accessible only to certain methods of that class.

Question 31

A constructor should return either True or False to determine if the object was initialized properly.

Question 32

Which of the following is the correct syntax for accessing the Public property Tire of an object named myCar outside of the Car class?

A)myCar(Tire)
B)myCar.Tire
C)myCar ->Tire
D)None of the above

Question 33

The _________ of a class are also called the public services or the public interface that the class provides to its clients.

A)public constructors
B)public instance variables
C)public methods
D)All of the above

Question 34

A class's initializes instance variables of that class.

A)constructor
B)utility method
C)access modifier
D)None of the above.

Question 35

You can create new reference types.

Question 36

You should not take into consideration that your code will be modified.

Question 37

The keyword _______ indicates that the method overrides an existing method with the same signature.

A)Replaces
B)Overrides
C)Overrules
D)Supersedes

Question 38

Every class inherits directly or indirectly from class _________ except for itself.

A)Inheritor
B)Base
C)VB
D)Object

Question 39

The purpose of utility methods is to support the operation of a class's other methods.

Question 40

Instance variables or methods declared with the modifier are accessible only in that class definition.

A)Protected
B)Shared
C)Private
D)None of the above.

Question 41

Programmers are encouraged to use method-parameter names that that are the same as instance variable names.

Question 42

Which of the following describes a Shared variable?

A)a variable with one copy shared by all class objects
B)a variable whose value may not be changed
C)all of the above
D)None of the above.

Question 43

Which of the following usages of the Me reference is syntactically correct (assume mHour is an instance variable of class CTime and the current object is an instance of CTime)?

A)Me.mHour
B)Me(CTime.mHour)
C)Me(CTime).mHour
D)None of the above.

Question 44

For properties that do not have any additional logic in their Set and Get accessors,__________ properties allow you to write one line of code and have the compiler generate the property's instance variable and accessors.

A)automatic
B)auto-implemented
C)auto-coded
D)None of the above

Question 45

The Me reference is used implicitly to refer to the instance variables,properties and methods of an object.

Question 46

Shared class variables have:

A)global scope
B)class scope
C)method scope
D)All of the above

Question 47

Only certain objects have a Me reference.

Question 48

While shadowing,programmers could use the This keyword and the dot separator to access the instance variable.

Question 49

Object initializers (which initialize an object and its properties)use what keyword?

A)Includes
B)Defined
C)With
D)Construct

Question 50

Outside a class's scope,class members cannot be referenced directly by name.

Question 51

Failure to release resources when the program is no longer using them can cause .

A)buffer overflows
B)resource leaks
C)exceptions
D)None of the above.

Question 52

Outside a class' scope,Public members can be accessed only by using the dot (. )operator.

Question 53

An object's Me reference refers to:

A)the object itself
B)what the programmer specified
C)the entry point of the program
D)None of the above.

Question 54

Me can be used to distinguish between a local variable and an instance variable that share the same name.

Question 55

When the number of references to an object becomes ,that object is marked for garbage collection.

A)low
B)zero
C)one
D)None of the above

Question 56

Having a Me reference allows:

A)A method to refer explicitly to the instance variables and other methods of the object on which the method was called.
B)A method to refer implicitly to the instance variables and other methods of the object on which the method was called.
C)An object to reference itself.
D)All of the above.

Question 57

An object initializer calls the default constructor before executing.

Question 58

Select the syntactically correct way to access a Public Shared class member.

A)className(sharedMemberName)
B)sharedMemberName.className
C)className.sharedMemberName
D)sharedMemberName(className)

Question 59

If you write the code Public Property Hour As Integer,the compiler would generate property code that would use the Private instance variable __________.

A)Hour
B)Hour_
C)_Hour_
D)_Hour

Question 60

In a method in which a parameter has the same name as an instance variable,the expression Me.name will refer to ________.

A)the parameter
B)the instance variable
C)varies depending on the situation
D)None of the above

Question 61

A Shared variable represents method-wide information.

Question 62

Attempting to modify the value of a Const variable at run time is a syntax error.

Question 63

Shared class members are available only after the first object of that class is created

Question 64

To access a Private Shared class member when no objects of the class exist,a Public Shared method or property must be provided.

Question 65

Const members can be initialized only to other constant values.

Question 66

Each object of a class has its own copy of all the instance variables of the class.

Question 67

The Object Brower _____________.

A)lists all the classes in the .NET library
B)describes the functionality provided by each specific class
C)is separated into three frames
D)All of the above.

Question 68

Data members declared as ReadOnly must be initialized in their declaration.

Question 69

A program contains a copy of a Shared variable for each object that is instantiated.

Question 70

Which of the following is not a keyword used to declare a constant variable:

A)Const
B)ReadOnly
C)NamedConst
D)None of the above

Question 71

Class Math provides only methods that perform common mathematical calculations.

Question 72

A Shared method has a Me reference.

Question 73

Constructors that are Shared can be defined to initialize only Shared members.

Question 74

A Shared method may access Shared and non-Shared members.

Question 75

All Math class methods are Shared and are therefore called by preceding the name of the method with the class name Math and a __________ separator.

A):
B),
C))
D)/

Question 76

Keyword is used for constants whose values cannot be determined at compile time.

A)Const
B)ReadOnly
C)Shared
D)None of the above.

Question 77

Const members must be initialized at compile time,but ReadOnly values are not initialized until runtime.Neither one can be modified once initialized.

Question 78

Variables that are Shared have class scope.

Question 79

You use the Object Browser to learn about the functionality provided by a specific class.

Question 80

Const members are not implicitly Shared.