Deck 17: Files and Streams

Question 1

The classes dealing with files and directories are located in the System.IO namespace.

Answer 1

True

Question 2

When a FileStream object is opened,the file-position pointer is _________.

A)set to Null
B) set to 0
C) needs to be explicitly created
D) set to the end of the file

Answer 2

B

Question 3

What exception is thrown when an error occurs during serialization or deserialization

A) SerialException
B) DeserialException
C) SerializationException
D) DeserializationException
E) c and d, respectively

Answer 3

C

Question 4

Which of the following methods of FileStream will reset the file-position pointer back to the beginning of the file

A)Reset
B) Origin
C) Seek
D) Beginning

Question 5

An OpenFileDialog allows a user to select a file to open.

Question 6

________ are used for long-term retention of large amounts of data.

A) Memory cards
B) Buffers
C) Files
D) Data structures

Question 7

Each resource should be released as soon as it's no longer needed.

Question 8

Console.In,Console.Out and Console.Error are used to take data in,to display data and to show error messages,respectively.

Question 9

What kind of exception is thrown if there's a problem opening or creating a StreamWriter

A)Exception
B) StreamException
C) OpenAndCreatingException
D) IOException

Question 10

BinaryFormatters can be used to serialize and deserialize objects coming in and going out via a stream.

Question 11

The FileAccess.Read enumeration member is used if the file should not be modified.

Question 12

A _____________ contains the byte number of the next byte in a file to be read or written to a file.

A) data locator
B) file counter
C) file-position pointer
D) byte-number counter.

Question 13

The standard output stream object enables a program to output data to the
screen.

Question 14

A serialized object is an object that includes:

A)a sequence of bytes that contain the object's data
B) information about the object's type
C) information about the types of data stored in the object
D) All of the above

Question 15

Use the _______ method of class OpenFileDialog to show a dialog that allows the user to select a file to be opened.

A) OpenFile
B) ChooseFile
C) ShowDialog
D) OpenFileDialog

Question 16

Data stored in a file is considered:

A) temporary data
B) persistent data
C) recurring data
D) there is no need to store data in files

Question 17

The enumeration FileAccess is used to:

A) control user access to a file
B) control program access to a file
C) control the amount of updating that can be done on a file at once
D) FileAccess is a method, not an enumeration

Question 18

Files can be stored in:

A) hard drives
B) optical disks
C) magnetic tapes
D) All of the above

Question 19

The Console.Error property returns:

A) a standard error stream object
B) a new error
C) an object of type error
D) None of the above

Question 20

When a file is opened,a stream object is created and associated with the file.

Question 21

Method GetFiles of class Directory can be used to display all the files in a given directory.

Question 22

Method ________ of class BinaryFormatter reads a serialized object from a stream and recreates the object in memory.

A) Deserial
B) Deserialize
C) Deserializable
D) DSerial

Question 23

.NET provides class _______ for manipulating files.

A) Folder
B) FileUtil
C) File
D) FileManip

Question 24

Class File can only create new files.

Question 25

Deserialize returns a reference of type:

A) object which must be cast to the appropriate type to manipulate the object
B) the type that the object was originally
C) Deserialized which must be cast to the appropriate type to manipulate the object
D) None of the above

Question 26

For variables of reference types,you must check the class declaration to ensure that the type is serializable.

Question 27

Class Directory is used to change directories.

Question 28

Which of the following attributes is needed to indicate to the CLR that objects of the class can be serialized

A)[Serializable]
B)[DeSerializable]
C)[Serialize]
D)both a and b

Question 29

If the array contains references to other objects,those objects may or may not be serializable.

Question 30

Directory's method GetDirectories returns:

A)a string of all the names of sibling directories
B) an array of strings of all the names of sibling directories
C) a string of all the names of subdirectories
D) an array of strings of all the names of subdirectories

Question 31

BinaryFormatter's Serialize and Deserialize methods are both parameterless.

Question 32

All simple-type variables and strings are serializable.

Question 33

To create a new file and return a stream that can be used to process the file,use the:

A) CreateFile method of class File
B) NewFile method of class File
C) Create method of class File
D) New method of class File

Question 34

A recursive search on a directory is one where:

A) a directory is searched and then all of its sub directories are searched.
B) each sub directory is searched and then the main directory is searched.
C) a search is done randomly on all directories.
D) a and c.
E) a and b

Question 35

By default,array objects are not serializable.

Question 36

In a class that's marked with the [Serializable] attribute or that implements inter
face ISerializable,not every instance variable of the class needs to be seri
alizable.

Question 37

Another way that a class could indicate to the CLR that objects of the class can be serialized is through implementing the ________ interface.

A)Serializable
B)ISerializable
C)Serial
D)Serialize

Question 38

BinaryFormatter allows only for reading objects.

Question 39

The name of the file to open is specified as the first argument to the FileStream constructor.