You work as an application developer at www.megaposts.net thet has been
hired by a small local private school to develop a class library that will be used in an
application named ManageAttendance for the purpose of managing student
records.
You are responsible for developing this class library.www.megaposts.net that has instructed
you to create a collection in the application to store learners’ results.
The school has informed you that they currently only have seven learners, but that
this value will triple in the following year. Due to the limited resources, you need to
ensure that the collection you create consumes a minimum amount of resources.
What should you use to create the collection?
A. The HybridDictionary collection class.
B. The HashTable collection class.
C. The ListDictionary collection class.
D. The StringCollection collection class.
.
.
.
Answer: A
Explanation: You should use the HybridDictionary class to create the collection
because this class is useful in scenarios where the number of elements is unknown or
could grow in size. A collection of the HybridDictionary type manages the collection
depending on the number of elements. The HybridDictionary type collection uses
the ListDictionary class to manage the collection when there are only a few
elements. When the number of elements exceeds ten, the HybridDictionary type
collection automatically converts the elements into HashTable management.
Incorrect Answers:
B: You should not use this collection class because this class is used if the total number
of elements to be stored in a collection is known and is greater than ten elements in
length.
C: You should not use this collection class because this class is used if the total number
of elements to be stored in a collection is known and is less than ten elements in length.
D: You should not use this collection class because this class is used to manage a
collection of string values.
QUESTION 10
You work as an application developer at www.megaposts.net that wants you to
develop an application that stores and retrieves client information by means of a
unique account number.
You create a custom collection class, which implements the IDictionary interface,
named ClientDictionary. The following code have been included into the new
application.
//Create Client objects
Client c1 = new Client (”AReid”, “Andy Reid”, Status.Current);
Client c2 = new Client (”DAustin”, “Dean Austin”, Status.New);
//Create ClientDictionary object
IDictionary cData = new ClientDictionary ();
cData.Add (”10001″, c1);
cData.Add (”10002″, c2);
You use the same method to add other Client objects to the collection. You need to
ensure that you are able to retrieve client information associated with the account
number 10111.
What should you do?
A. Use the following code:
Client foundClient;
foundClient = (Client) cData.Find (”10111″);
B. Use the following code:
Client foundClient;
if (cData.Contains (”10111″))
foundClient = cData ["10111"];
C. Use the following code:
Client foundClient;
if (cData.Contains (”10111″))
foundClient = (Client) cData ["10111"];
D. Use the following code:
Client foundClient;
foreach (string key in cData.Keys
{
if (key == “10111″)
foundClient = (Client) cData.Values ["10111"];
}
.
.
.
Answer: C
Explanation: This code invokes the Contains method of the IDictionary interface to
determine whether a value is associated with the key 10111. If a value exists for that
key, then the clientData ["10111"] statement retrieves the client data as a generic
object. The code casts the generic object into a Client object, and it is stored in the
foundClient variable
Incorrect Answers:
A: You should not use the code that uses the Find method because no such method exists
in the IDictionary interface.
B: You should not use the code that assigns the foundClient variable to a generic
object because the foundClient variable is declared as a Client type.
D: You should not use the code that iterates through the Keys collection because it is
unnecessary and process-intensive.
QUESTION 11
You work as an application developer at www.megaposts.net that has
instructed you to create a class named MetricFormula. This class will be used to
compare MetricUnit and EnglishUnit objects.
The MetricFormula is currently defined as follows (Line numbers are used for
reference purposes only):
1. public class MetricFormula
2. {
3.
4. }
You need to ensure that the MetricFormula class can be used to compare the
required objects.
What should you do? (Choose two)
A. Add the following code on line 1:
: IComparable
{
B. Add the following code on line 1:
: IComparer
{
C. Add the following code on line 3:
public int Compare (object x, object y)
{
// implementation code
}
D. Add the following code on line 3:
public int CompareTo (object obj)
{
// implementation code
}
.
.
.
Answer: B, C
Explanation: You should add the code so that it reads as follows:
1. public class MetricFormula : IComparer
2. {
3. public int Compare (object x, object y)
4. {
5. // implementation code
5. }
6. }
You have to implement the IComparer interface to create a comparer class for MetricUnit
and EnglishUnit objects. The IComparer interface provides only one method named
Compare. The Compare method takes two objects and returns an integer value
representing whether those objects are equal, greater than, or less than the other. If the
return value is negative, then the first object is less than the second. The objects are equal
if the return value is zero. The first object is greater than the first if the return value is
positive. The IComparer interface is typically used if you want to implement comparison
across objects of different classes without having to provide implementation in each
comparable class.
Incorrect Answers:
A, D: You should use these two options because this should be implemented by the
MetricUnit and EnglishUnit classes.
Refrence :MCTS 70-536 Question Bank
PR: 
LD: 
I: 
C: 
SD: 
