Lesson 2

Question 1

objects

Answer 1

self-contained data structures that consist of properties, methods, and events. Properties specify the data represented by an object (adjective), methods specify an object’s behavior (actions or verbs), and events provide communication between objects.

Question 2

encapsulation

Answer 2

Hiding the complexity of code inside something.

Question 3

class (context of object oriented programming)

Answer 3

a class is like the template from which individual objects are created.

Question 4

another name for object:

Answer 4

instance of a class

Question 5

method

Answer 5

code blocks containing a series of statements

Question 6

constructors

Answer 6

used to initialize the data members of the object.

Question 7

How are objects created?

Answer 7

From the templates defined by classes.

Question 8

What is the use of properties?

Answer 8

Allow you to access class data in a safe and flexible way.

Question 9

access modifier

Answer 9

specifies what region of the code will have access to a field.

Question 10

method’s signature

Answer 10

a method’s name, its parameter list, and the order of data types of the parameters. A method’s signature must be unique within a class.

Question 11

default constructor

Answer 11

a constructor that takes no arguments

Question 12

What is the method line format?

Answer 12

access level - return type - method name - parameters in parentheses - followed by a block of code in curly braces.

Question 13

What are properties?

Answer 13

class members that can be accessed like data fields, but contain code like a method.

Question 14

types of accessors:

Answer 14

get - used to return the property value.

set - used to assign a new value to the property.

Question 15

When defining properties, a missing set accessor causes what?

Answer 15

You don’t provide a way to set the value of the property, and it becomes read-only as a result.

Question 16

When defining properties, a missing get accessor causes what?

Answer 16

You don’t provide a way to get the value of the property, and it becomes write-only as a result.

Question 17

auto-implemented properties

Answer 17

simplify property declarations

Question 18

“this” keyword use

Answer 18

accesses members from within constructors, instance methods, and accessors of instance properties.

Question 19

delegates

Answer 19

special types that are used to encapsulate a method with a specific signature. They’re like an agreement or a contract between a publisher and a subscriber. It determines the signature of the event handler method in the subscriber.

Question 20

events

Answer 20

a way for a class to notify other classes or objects when something of interest happens.

Question 21

publisher

Answer 21

the class which sends the notification to the subscriber during an event.

Question 22

subscriber

Answer 22

the class which receives the notification from the publisher during an event.

Question 23

two pieces of information needed when defining events:

Answer 23

a delegate that connects the event with its handler method(s), and a class that contains the event data. (Usually derived from the EventArgs class)

Question 24

What is the purpose of a namespace?

Answer 24

It allows you to organize code and create unique class names.

Question 25

static members

Answer 25

belong to a class itself rather than individual objects.

Question 26

What does a value type do?

Answer 26

It directly stores a value.

Question 27

What does a reference type do?

Answer 27

It stores only a reference to a memory location, not the value itself.

Question 28

What is the keyword “struct” used for?

Answer 28

To create a user-defined data types that consist of small groups of related fields. Structs are value types - as opposed to classes, which are reference types. They cannot inherit from another class or struct.

Question 29

access modifiers

Answer 29

control where a type or type member can be used.

Question 30

assembly

Answer 30

a unit of executable code that can be independently versioned and installed.

Question 31

base class

Answer 31

the class whose functionality is inherited.

Question 32

derived class

Answer 32

The class that inherits the functionality from a base class

Question 33

abstract classes

Answer 33

provide a common definition of a base class that can be shared by multiple derived classes.

Question 34

sealed classes

Answer 34

provide complete functionality but cannot be used as base classes.

Question 35

polymorphism

Answer 35

the ability of derived classes to share common functionality with base classes but still define their own unique behavior.

Question 36

keyword “virtual” use

Answer 36

allows for the derived classes to override the method.

Question 37

keyword “override” use

Answer 37

replaces a base class member in a derived class

Question 38

keyword “new” use

Answer 38

creates a new member of the same name in the derived class and hides the base class implementation

Question 39

interface use

Answer 39

to establish contracts through which objects can interact with each other without knowing the implementation details.