Deck 5: Loops, Files, and Random Numbers

Question 1

The third expression appearing in the header of a for loop is the ____________, which executes at the end of each iteration. It usually increments the loop's counter variable.

A) test expression
B) update expression
C) initialization expression
D) increment expression

Answer 1

B

Question 2

The ____________ is specifically designed for situations requiring a counter variable to control the number of times a loop iterates.

A) while loop
B) if-else statement
C) for loop
D) switch statement

Answer 2

C

Question 3

The increment operator is ____________.

A) --
B) ++
C) -=
D) +=

Answer 3

B

Question 4

Each time a loop executes its statement or statements, we say the loop is performing a(n) ____________.

A) cycle
B) pass
C) execution
D) iteration

Question 5

ListBox controls have an ____________ property that reports the number of items stored in the ListBox.

A) Items.Count
B) Items.Size
C) Items.List
D) Items.Contains

Question 6

The ____________ begins with the word while, followed by a Boolean expression that is enclosed in parentheses.

A) conditional statement
B) logic mark
C) while clause
D) loop parameter

Question 7

The first expression appearing in the header of a for loop is the ____________, which usually assigns a starting value to a counter variable.

A) update expression
B) test expression
C) Boolean expression
D) initialization expression

Question 8

To add an item to a ListBox control with code, you call the control's ____________method.

A) Add.Items
B) Items.Add
C) Items.Append
D) Items.Insert

Question 9

ListBox controls have an ____________ method that erases all the items in the Items property.

A) Items.Erase
B) Items.Remove
C) Items.Clear
D) Items.Reset

Question 10

To ____________ a variable means to increase its value by 1.

A) append
B) decrement
C) add
D) increment

Question 11

To ____________ a variable means to decrease its value by 1.

A) subtract
B) increment
C) decrement
D) supplement

Question 12

The while loop is known as a ____________, which means it tests its condition before performing each iteration.

A) posttest loop
B) pretest loop
C) proactive loop
D) preemptive loop

Question 13

____________ are commonly used to control the number of times a loop iterates.

A) Boolean variables
B) Sentinel variables
C) Counter variables
D) Named constants

Question 14

The ++ and -- operators can be written before their operands, which is called ____________.

A) preface mode
B) postfix mode
C) prefix mode
D) superscript mode

Question 15

The statement or block of statements following the while clause is known as the ____________ of the loop.

A) assembly
B) body
C) definition
D) sequence structure

Question 16

The second expression appearing in the header of a for loop is the _____________, which is a Boolean expression that determines whether the loop will repeat.

A) test expression
B) update expression
C) initialization expression
D) control expression

Question 17

The decrement operator is ____________.

A) +=
B) --
C) -=
D) ++

Question 18

If a loop does not have a way of stopping, it is called a(n) ____________.

A) runaway loop
B) game loop
C) infinite loop
D) expressionless loop

Question 19

When the ++ and -- operators are written after their operands it is called ____________.

A) prefix mode
B) suffix mode
C) appendix mode
D) postfix mode

Question 20

Because the for loop tests its Boolean expression before it performs an iteration, it is a ____________.

A) pretest loop
B) pseudo loop
C) posttest loop
D) infinite loop

Question 21

In order to write data to a text file, you must create a file object using the ____________.

A) TextReader class
B) TextWriter class
C) StreamReader class
D) StreamWriter class

Question 22

The ____________ is a method in by the StreamWriter class that writes an string to a text file without writing a newline character.

A) Print method
B) Text method
C) WriteLine method
D) Write method

Question 23

A ____________ contains data that has been encoded as text using a scheme such as ASCII.

A) document (as on MS-Word or Open-Document Format)
B) spreadsheet (as in Excel)
C) binary file
D) text file

Question 24

When you want to read data from a text file, you create a file object using the ____________.

A) StreamReader class
B) TextReader class
C) BufferedReader class
D) InputReader class

Question 25

The ____________ is a posttest loop, which means it performs an iteration before testing its Boolean expression.

A) for loop
B) while loop
C) do-while loop
D) do-before loop

Question 26

If you specify a path in a string literal, be sure to prefix the string with the ____________ symbol, also known as the literal text character.

A) #
B) @
C) $
D) *

Question 27

When you work with a ____________, you process data from the beginning of the file to the end of the file.

A) sequential access file
B) direct access file
C) text file
D) input file

Question 28

Files on disk are identified by a(n) ____________.

A) index
B) filename
C) access number
D) binary signature

Question 29

Many systems, including MS-Windows, support the use of ____________, which are short sequences of characters that appear at the end of filenames and are preceded by a period.

A) filename extensions
B) pragmatic identifiers
C) binary indices
D) run time signatures

Question 30

A ____________, is an object associated with a specific file and provides a way for the program to work with that file.

A) data object
B) file object
C) Filename class
D) referential extension

Question 31

You can use the StreamWriter class's ____________ method to write a line of text to a file.

A) PrintLine
B) WriteText
C) WriteLine
D) PrintText

Question 32

The term ____________ is used to describe a file to which data is written.

A) input file
B) output file
C) record file
D) recordset

Question 33

You can use the StreamReader class's ____________ method to read a line of text from a file.

A) ReadLine
B) ReadText
C) GetNext
D) Read

Question 34

Be careful not to place a statement that modifies the counter variable inside the body of a ____________.

A) while loop
B) if statement
C) for loop
D) switch statement

Question 35

When you work with a ____________, you can jump directly to any piece of data in the file without reading the data that comes before it.

A) file object
B) binary file
C) direct access file
D) sequential access file

Question 36

To append data to an existing file, you open it with the ____________ method.

A) File.Append
B) File.AppendAll
C) File.AppendText
D) File.OpenExistingText

Question 37

The term ____________ is used to describe a file from which data is read.

A) input file
B) output file
C) record file
D) recordset

Question 38

A ____________ contains data that cannot be viewed by a text editor (such as NotePad).

A) source file
B) binary file
C) data file
D) save file

Question 39

A ____________ character is an invisible character that marks the end of a line of text.

A) line feed
B) newline
C) line marker
D) startline

Question 40

In the header of a for loop, which expression should not end with a semicolon?

A) initialization expression
B) test expression
C) update expression
D) none of these

Question 41

The ____________ allows the user to browse the system and select a location and name for a file that is about to be saved.

A) Save As dialog box
B) Save File dialog box
C) Select Source dialog box
D) Open dialog box

Question 42

The .NET Framework provides a class named ____________ that you can use in C# to generate random numbers.

A) Rand
B) Random
C) GenNum
D) RandomGenerator

Question 43

In code, you can display a Save As dialog box by calling the SaveFileDialog control's ____________ method.

A) SaveAs
B) Show
C) ShowDialog
D) Display

Question 44

When controls such as the OpenFileDialog and SaveFileDialog are created, they do not appear on the form, but in an area at the bottom of the Designer known as the ____________.

A) control overflow
B) design space
C) component tray
D) virtual form

Question 45

If the user clicks the Cancel button, the SaveFileDialog control's ShowDialog method returns the value ____________.

A) Result.False
B) DialogResult.Cancel
C) DialogResult.Abort
D) Result.NULL

Question 46

The expression ____________ causes an object of the Random class to be created in memory.

A) GetRandom(int)
B) GenerateRandom(number)
C) new Random()
D) random new()

Question 47

A file's ____________ marks the location of the next item that will be read from the file.

A) line marker
B) index value
C) read position
D) newline character

Question 48

You can specify the directory to be initially displayed by the Open dialog box by storing its path in the ____________.

A) InitialDirectory property
B) Source property
C) Filename property
D) Path property

Question 49

The ____________ displays a standard Windows Save As dialog box.

A) SaveAs method
B) SaveFileDialog control
C) Save_File event
D) OpenFileDialog control

Question 50

You can call a Random object's ____________ method to get a random floating-point number between 0.0 and 1.0.

A) GetDouble
B) NextFloat
C) NextDouble
D) DoubleRand

Question 51

If the user clicks the Open button, the OpenFileDialog control's ShowDialog method returns the value ____________.

A) Result.True
B) DialogResult.OK
C) DialogResult.Open
D) Result.OpenFile

Question 52

Once you have created a Random object, you can call its ____________ method to get a random integer number.

A) Next
B) GetInteger
C) GenerateNumber
D) NextInteger

Question 53

The ____________ displays a standard Windows Open dialog box.

A) Open method
B) OpenFileDialog control
C) FindFileDialog control
D) SelectFile control

Question 54

The variable that accumulates a total of the numbers in a running total is called a(n) ____________.

A) counter
B) sentinel
C) entity
D) accumulator

Question 55

The numbers generated by the Random class are ____________calculated by a formula.

A) pseudorandom numbers
B) binary encoded numbers
C) algebraic derivatives
D) complex variables

Question 56

You can use the StreamReader class's ____________ to determine if the file's read position is at the end of the file.

A) EndOfFile property
B) StreamEnd method
C) EndOfStream property
D) EOF method

Question 57

A(n) ____________ accumulates a total by adding each number in a series to a variable that holds the sum.

A) running total
B) numeric tally
C) active summary
D) dynamic collection

Question 58

When the user selects a file with the Open dialog box, the file's path and filename are stored in the control's ____________.

A) FilePath property
B) Source property
C) Location property
D) Filename property

Question 59

The ____________ is useful in applications that must open an existing file because it allows the user to browse the system and select the file.

A) File.OpenText method
B) OpenFileDialog control
C) Open dialog box
D) Windows Explorer

Question 60

You can change the default text displayed in the Open dialog box's title bar by changing the control's ____________.

A) Caption property
B) Text property
C) Title property
D) Heading property

Question 61

You can only add values of the string data type to a ListBox control.

Question 62

The ++ operator is pronounced "plus plus" and the -- operator is pronounced "minus minus".

Question 63

The while loop gets its name from the way it works: While a Boolean expression is true, do some task.

Question 64

When a variable is declared in the initialization expression of a for loop, the scope of the variable is limited to the loop.

Question 65

Counter variables are commonly used to hold Boolean values that control the number of times a loop iterates.

Question 66

By indenting the statements in the body of a loop, you visually set the loop body apart from the surrounding code.

Question 67

When you write a stand-alone statement to increment a variable, the prefix operator is faster than the postfix version.

Question 68

In a counter-controlled loop, you can only decrement the counter variable.

Question 69

A ____________ is used in the calculation to generate random numbers.

A) sentinel
B) logarithmic value
C) seed value
D) Random object

Question 70

Incrementing and decrementing are so commonly done in programs that C# provides the ++ and -- unary operators for just these purposes.

Question 71

Not only may the counter variable of a for loop be initialized in the initialization expression, but it may also be declared there.

Question 72

A while loop will always iterate at least once, even if the Boolean expression is initially false.

Question 73

In the update expression of a for loop, you must use the ++ operator in the increment expression.

Question 74

When you run an application, the application's form is loaded into memory and an event known as the ____________ takes place.

A) Load event
B) Launch event
C) Boot event
D) Initialization event

Question 75

If a ListBox is empty, the Items.Count property equals −1.

Question 76

If you are writing a while loop that has only one statement in its body, you do not have enclose the statement inside curly braces.

Question 77

The first line of the for loop is known as the loop title.

Question 78

The do-while loop always performs at least one iteration, even if its Boolean expression is false to begin with.

Question 79

It is possible to write a for loop in such a way that it will never iterate.

Question 80

In most circumstances you should avoid writing loops that never-end.