Deck 11: Exception Handling

Question 1

Errors you discover when compiling a program are considered to be exceptions.

Answer 1

False

Question 2

All classes in the C# programming language, including the Exception class, are descendants of what built in class?

A) System
B) Application
C) CLR
D) Object

Answer 2

D

Question 3

In general, what block do you use to perform clean-up tasks that must occur, regardless of whether any errors occurred or were caught?

A) default block
B) always block
C) execute block
D) finally block

Answer 3

D

Question 4

You can deliberately generate a SystemException by forcing a program to contain an error.

Question 5

A block that contains statements that can never execute under any circumstances due to a program's logic is known as what kind of block?

A) default block
B) comment block
C) finally block
D) unreachable block

Question 6

What represents the degree to which a system is resilient to stress and able to maintain correct functioning?

A) fault tolerance
B) critical functionality
C) load forgiveness
D) system robustness

Question 7

What method can be used to terminate an application?

A) Environment.Exit()
B) Environment.Bye()
C) Environment.Quit()
D) Environment.Terminate()

Question 8

What read-only property in the Exception class contains useful information about an Exception object?

A) StackTrace
B) Message
C) toString
D) ThrownText

Question 9

When writing a block of code in which something can go wrong, where should you place the block?

A) It should be placed in a try block.
B) It should be placed after a catch statement.
C) It should be prefaced with a finally statement.
D) It should be defined as an exception block.

Question 10

According to the creators of C#, an infrequent event in code is one that happens in less than what percent of all program executions?

A) 10%
B) 25%
C) 30%
D) 35%

Question 11

A catch block can catch how many types of Exceptions?

A) An unlimited number of Exception types.
B) Only one can be caught.
C) As many as can be matched.
D) Two, after which the program ends.

Question 12

In C#, all exceptions are objects that are members or derived members of what specific class?

A) ApplicationException
B) Exception
C) SystemException
D) RuntimeException

Question 13

What method is overridden by the Exception class in order to provide a descriptive error message and provide a user with precise information about the nature of any Exception that is thrown?

A) Message()
B) StackTrace()
C) ToString()
D) ThrownMessage()

Question 14

An exception belonging to what specific class is thrown when an attempt is made to store an element of the wrong type within an array?

A) System.ArrayTypeMismatchException
B) System.TypeMismatch
C) System.FormatException
D) System.InvalidCastException

Question 15

You can place any number of statements in a try block, including those you know will never throw an exception.

Question 16

What methods are used to convert string data to another data type, such as int, double, or bool, without fear of generating an exception?

A) TryData()
B) TryFromString()
C) TryParse()
D) TryConvert()

Question 17

An exception of the ____ class is thrown when an ongoing operation is aborted by the user.

A) System.InvalidOperationException
B) System.ArithmeticException
C) System.Data.OperationAbortedException
D) System.InvalidCastException

Question 18

What block can you use to ensure that input and output related files are properly closed?

A) execute
B) always
C) finally
D) default

Question 19

C# has more than 100 defined Exception subclasses.

Question 20

If you are working on a professional project, Microsoft recommends that you use the general Exception class in a catch block.

Question 21

The StackTrace property of an Exception can be a useful debugging tool.How is this property used when debugging?

Question 22

The ApplicationException class is a sublcass of what other class?

A) SystemException
B) Exception
C) ObjectException
D) MainException

Question 23

What class should you extend in order to create your own Exception that you can throw?

A) ApplicationException
B) ExceptionObject
C) SystemException
D) Object

Question 24

When creating an Exception class, what is not one of the three recommended constructors needed?

A) A default constructor.
B) A constructor that takes a string message.
C) A constructor that takes a string message and an inner exception.
D) A constructor that takes a byte variable containing memory dumps.

Question 25

The following example shows how a programmer might avoid a division by zero error by explicitly checking for the error condition:
if(gallonsOfGas != 0)
mpg = milesDriven /gallonsOfGas;
else
mpg = 0;
Another possible way to deal with this is to use exception handling mechanisms.What factors help the programmer decide which of these methods to use?

Question 26

The int version of the TryParse() methods converts string data to an int.The first argument is the string that you want to convert, and the second argument is an out parameter that receives the result if the conversion is successful, or 0 if it is not.The method returns a Boolean value that indicates whether the conversion was successful.Write this method using exception handling techniques to ensure that the method returns correctly whether or not the conversion is successful.Use the method Convert.ToInt32(inputString) to do the conversion.

Question 27

When you catch an Exception, what property holds a list of methods in the call stack as its value, allowing you to determine the location of the Exception?

A) StackTrace
B) CallTrace
C) MethodTrace
D) ClassTrace

Question 28

The Environment.Exit() method is part of what namespace?

A) Exception
B) System
C) Quit
D) Language

Question 29

Most exceptions that are used by programmers derive from three C# classes.What are those classes?

Question 30

What type of exception is thrown if there is an issue with file operations, such as opening, reading from, or writing to a file?

A) FileException
B) StorageException
C) FException
D) IOException

Question 31

When an Exception object is thrown and multiple catch blocks are present, what happens?

Question 32

If a finally block is associated with a try…catch pair, what are the three possible outcomes of the try that result in execution of the finally block?

Question 33

When you write a method that catches an Exception, rather than handling the Exception itself, it can pass the exception to the method that called your method.What is this known as?

A) rethrowing the Exception
B) saving the Exception
C) opening the Exception
D) sideloading the Exception

Question 34

Show the syntax (the general form) of a try…catch pair.

Question 35

When you design classes containing methods that have statements that might throw exceptions, you can create the methods so they throw the Exception object but do not handle it.Why might you want to do this?

Question 36

What happens when you divide a floating-point value by 0 in C#?

A) No exception occurs, and the special value Infinity is returned as the result.
B) The program will throw an exception of type System.DivideByZeroException.
C) The program will catch the exception, and return Undefined as the result.
D) The program will crash.

Question 37

What is the system of passing an exception through a chain of calling methods called?

A) propagating the exception
B) tracing the exception
C) stacking the exception
D) inheriting the exception

Question 38

The memory location where the computer stores the list of locations to which the system must return is known by what term?

A) The method call trace.
B) The memory call pool.
C) The call stack.
D) The function call.

Question 39

Why might a finally block be necessary?