Deck 14: Files and Streams

Question 1

When you store data in a computer file on a persistent storage device, what are you doing?

A) You are reading from the file.
B) You are using an input stream.
C) You are writing to the file.
D) You are flashing the data to memory.

Answer 1

C

Question 2

The terms directory and folder are used synonymously to refer to an entity that is used to organize files.

Answer 2

True

Question 3

Files exist on devices such as hard disks, USB drives, reels of magnetic tape, and optical discs.What are these files considered to be?

A) temporary files
B) volatile files
C) soft files
D) permanent files

Answer 3

D

Question 4

Most computer users organize their files into directories, which are also known by what term?

A) folders
B) bins
C) buckets
D) drawers

Question 5

How does a C# application open a file?

A) It opens a file by associating the file with a memory address.
B) It opens a file by reading the contents into RAM and storing them internally as a string.
C) It opens a file by creating an object and associating a stream of bytes with that object.
D) It opens a file by reading each line of a file into an array.

Question 6

The File class is contained in the System.IOFile namespace.

Question 7

When a C# application is done using a file, what should it do with the file?

A) It should delete the file.
B) It should return the file to RAM.
C) It should truncate the file.
D) It should close the file.

Question 8

When you copy data from a file on a storage device into RAM, what are you doing?

A) You are writing to the file.
B) You are reading from the file.
C) You are copying to the file.
D) You are flashing the data to memory.

Question 9

Permanent storage that does not lose contents when a computer loses power is known as what type of storage?

A) volatile
B) temporal
C) nonvolatile
D) soft storage

Question 10

A CSV file contains values separated by semicolon delimiters.

Question 11

A data file is what type of file when each record is read in order of its position in the file?

A) sequential access file
B) random access file
C) dynamic read file
D) temporary buffer file

Question 12

What is a collection of fields that contain data about an entity?

A) a file
B) a character
C) a record
D) a bit

Question 13

When you write a program and save it to a disk, you are using temporary storage.

Question 14

What class contains methods that allow you to access information about files?

A) Cabinet
B) File
C) Directory
D) Folder

Question 15

Files are used to store data on nonvolatile memory.

Question 16

What class can be used to provide information on directories or folders?

A) Directory
B) File
C) Cabinet
D) Folder

Question 17

Due to the fact that data can be erased from files, what term do programmers generally prefer over permanent storage?

A) volatile storage
B) temporary storage
C) transit storage
D) persistent storage

Question 18

What format is used by files that store music or images?

A) data
B) binary
C) text
D) information

Question 19

When you write a C# program that stores a value in a variable, you are using temporary storage; the value you store is lost when the program ends or the computer loses power.What is the name for this kind of storage?

A) volatile
B) nonvolatile
C) permanent
D) hard

Question 20

What term describes any one of the letters, numbers, or other special symbols (such as punctuation marks) that comprise data.

A) field
B) record
C) delimiter
D) character

Question 21

When you perform an input operation in an application, the bytes flowing into your program from an input device typically are pictured by programmers as what?

A) A directory filling and emptying.
B) A stream of information.
C) A bucket filling with water.
D) A chunk of information.

Question 22

Approximately how many bytes are in a gigabyte?

A) a thousand bytes
B) a million bytes
C) a billion bytes
D) a trillion bytes

Question 23

What file mode is used to open an existing file, and empty the file once opened so that the file is zero bytes in size?

A) Append
B) Empty
C) Truncate
D) Destroy

Question 24

What Filestream property indicates whether the Filestream supports reading?

A) ReadAccess
B) CanRead
C) CanSeek
D) CanWrite

Question 25

Sometimes it is necessary to process a sequential text file multiple times from the beginning during a program's execution.After the file is processed the first time, the file pointer is at the end of the file.How can you reread the file at this point?

Question 26

The FileStream class has 15 overloaded constructors.What can you tell about the FileStream object named myFile, given the constructor below?
FileStream myFile =
new FileStream("SomeText.txt", FileMode.Create,
FileAccess.Write);

Question 27

If you attempt to open a file with the Open file mode, what happens if the file does not exist?

A) The file is created and then opened for use.
B) The program returns a prompt to the user asking if the file should be created.
C) The program will return a null object, and all data written to the file will be discarded.
D) The program throws a System.IO.FileNotFoundException error.

Question 28

What must be done in order to convert streams of bytes back into objects?

A) deserialization
B) serialization
C) normalization
D) denormalization

Question 29

What method is a member of the String class and takes a character delimiter parameter and separates a string into substrings at each occurrence of the delimiter?

A) Separate()
B) Split()
C) Delimit()
D) Substring()

Question 30

Describe some of the methods of the Directory class.

Question 31

What is a character?

Question 32

Hardcoding numbers (unnamed, literal constants) in code without explanation is a bad programming practice.What are these hardcoded numbers known as?

A) constant issues
B) token numbers
C) magic numbers
D) character sets

Question 33

When you produce screen output and accept keyboard input, you use the Console class, which provides access to which three standard streams?

Question 34

What is the process of converting objects into streams of bytes known as?

A) deserialization
B) normalization
C) streaming
D) serialization

Question 35

When a file is open in C#, what holds the byte number of the next byte to be read?

A) the file token
B) the file position pointer
C) the magic number
D) the record token

Question 36

What is a record?

Question 37

What are the disadvantages to writing data to a text file using tokens and delimiters as opposed to writing an entire object to a file at once?

Question 38

Write a program that prompts a user for a filename and tests the file's existence.If the file exists, display the file creation time.If it does not exist, display a message.

Question 39

How can you create a class whose objects can be written to and read from data files? Show an example.

Question 40

A program that reads from a sequential access data file creates a FileStream object, and then the FileStream object is passed to a StreamReader object's constructor.Once this has been done, the ReadLine() method can be used to retrieve one line at a time from the data file.Show the sequence of instructions that would create the FileStream and StreamReader needed to access a data file, and then read one line from the file.