Basic C# .Net Quiz 2
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myArray[1][3];
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myArray[1,3];
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myArray{1}{3};
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myArray(1),(3);
To output the value of a multidimensional array, you need to provide the indices for each dimension of the array. Let's go through each option and determine if it correctly outputs the value of a multidimensional array:
A. myArray[1][3]; This option is incorrect because it uses the wrong syntax to access the value of a multidimensional array. In C#, the correct syntax to access a value in a multidimensional array is myArray[1,3], not myArray[1][3]. The correct syntax uses commas to separate the indices for each dimension.
B. myArray[1,3]; This option is correct. It uses the correct syntax to access the value of a multidimensional array. The comma is used to separate the indices for each dimension, and this syntax correctly outputs the value at index 1 in the first dimension and index 3 in the second dimension of the array.
C. myArray{1}{3}; This option is incorrect because it uses curly braces instead of square brackets to access the value of the multidimensional array. In C#, square brackets [] are used to access array elements, not curly braces {}.
D. myArray(1),(3); This option is incorrect because it uses parentheses instead of square brackets to access the value of the multidimensional array. In C#, square brackets [] are used to access array elements, not parentheses ().
Therefore, the correct option is B. myArray[1,3].
All methods in an abstract base class must be declared abstract.
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True
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False
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True
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False
The code public class B : A { }
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Defines a class that inherits all the methods of A
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Defines a class that inherits the public and protected methods of A only
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Errors
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a and b
AI Explanation
To answer this question, let's go through each option to understand why it is correct or incorrect:
Option A) Defines a class that inherits all the methods of A - This option is incorrect because it states that class B inherits all the methods of A. However, without any additional information, we cannot determine if class B indeed inherits all the methods of class A.
Option B) Defines a class that inherits the public and protected methods of A only - This option is correct. In C#, when a class is derived from another class (using the colon syntax), it inherits the public and protected members of the base class. In this case, class B inherits the public and protected methods of class A.
Option C) Errors - This option is incorrect because there is no apparent error in the given code. It is a valid class definition.
Option D) a and b - This option is incorrect because only option B is correct. Option A is incorrect because it assumes that class B inherits all the methods of class A, which is not necessarily true.
The correct answer is B) Defines a class that inherits the public and protected methods of A only. This option is correct because when a class is derived from another class in C#, it inherits the public and protected members of the base class.
Assuming that public class B : A { public B(int i) :base(i) { } } compiles and runs correctly, what can we conclude about the constructors in the class A?
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One constructor takes an argument of type i
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There is only a default constructor
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One constructor takes an arguments of the type int
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a and b
AI Explanation
To answer this question, let's analyze the given code:
public class B : A {
public B(int i) : base(i) {
}
}
This code snippet shows the class B inheriting from class A. The constructor in class B takes an argument of type int and calls the base constructor of class A with the same argument.
Based on this information, we can conclude that:
A. One constructor takes an argument of type i - This option is incorrect because the argument in the constructor of class B is named i, not i itself.
B. There is only a default constructor - This option is incorrect because the presence of the B(int i) constructor in class B indicates that there is a non-default constructor in class A.
C. One constructor takes an argument of the type int - This option is correct because the B(int i) constructor in class B calls the base constructor A(int i), indicating that there is a constructor in class A that takes an argument of type int.
D. a and b - This option is incorrect because option A is incorrect. Only option C is correct.
Therefore, the correct answer is option C.
A Thread is:
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an object that allows computer multitasking
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an object that wraps itself with other threads
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a deprecated object that is no longer used
Synchronization is:
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the delaying of a thread until there is sufficient memory and work to keep it up
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making every thread start and end at the same time
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make each thread do the same thing
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have each thread start at the same time but not necessarily finish together
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wait until the required resources, that are used by other threads become available
AI Explanation
To answer this question, we need to understand the concept of synchronization in the context of threads.
Synchronization is a mechanism used in concurrent programming to control the access to shared resources by multiple threads. It ensures that only one thread can access a shared resource at a time, preventing data inconsistencies and race conditions.
Let's go through each option to understand why it is correct or incorrect:
Option A) the delaying of a thread until there is sufficient memory and work to keep it up This option does not accurately describe synchronization. Synchronization is not related to memory availability or workload.
Option B) making every thread start and end at the same time This option does not accurately describe synchronization. Synchronization is not about controlling the starting and ending times of threads.
Option C) make each thread do the same thing This option does not accurately describe synchronization. Synchronization is about coordinating the access to shared resources, not making threads do the same thing.
Option D) have each thread start at the same time but not necessarily finish together This option partially describes synchronization, but it is not complete. Synchronization is not only about starting threads at the same time; it also involves coordinating access to shared resources.
Option E) wait until the required resources, that are used by other threads, become available This option accurately describes synchronization. Synchronization involves waiting for the required resources to become available before accessing them to prevent data inconsistencies.
The correct answer is E) wait until the required resources, that are used by other threads, become available. This option accurately describes the concept of synchronization in the context of concurrent programming.
In C# Thread.Sleep(time) measures time in:
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seconds
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milliseconds
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nanoseconds
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all of the above
When a thread returns from a WaitSleepJoin or Suspended state it returns to the:
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Unstarted state
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Stopped state
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Started state (now considering a part of the running state)
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Resume state
The ThreadPriority enumeration does not contain:
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Lowest
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Highest
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BelowNormal
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None of the above
AI Explanation
To answer this question, we need to understand the ThreadPriority enumeration in programming.
The ThreadPriority enumeration represents the priority levels that can be assigned to a thread in a multi-threaded application.
Let's go through each option to understand why it is correct or incorrect:
Option A) Lowest - This option is incorrect because the ThreadPriority enumeration does contain the Lowest priority level. The Lowest priority represents the lowest priority level that can be assigned to a thread.
Option B) Highest - This option is incorrect because the ThreadPriority enumeration does contain the Highest priority level. The Highest priority represents the highest priority level that can be assigned to a thread.
Option C) BelowNormal - This option is incorrect because the ThreadPriority enumeration does contain the BelowNormal priority level. The BelowNormal priority represents a priority level lower than Normal but higher than Lowest.
Option D) None of the above - This option is the correct answer because all of the options A, B, and C are incorrect. The ThreadPriority enumeration does contain the Lowest, Highest, and BelowNormal priority levels.
The correct answer is D. None of the above.
String indexers treat strings as:
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binary code
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1 to string Length
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arrays of characters
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a character
To solve this question, the user needs to know the concept of string indexers.
String indexers treat strings as arrays of characters, where each character in the string is assigned an index value based on its position.
Option A is incorrect because string indexers do not treat strings as binary code.
Option B is incorrect because the index values assigned to characters in a string do not start from 1 and go up to the length of the string. They start from 0 and go up to length-1.
Option C is correct because string indexers treat strings as arrays of characters.
Option D is incorrect because a string is made up of multiple characters, not just one.
Therefore, the correct answer is: C. arrays of characters.
If an IndexofAny method is passed an array of characters it:
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finds the first occurrence of each letter in the string
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searches for the first occurrence of any of the characters in the string
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will search for the first occurrence of the sequence of characters
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generates an error
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reserved words
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method calls
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operator overloading
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operator overloading and method calls
If two StringBuilder objects contain the same string then
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they represent the same meory location
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the are two different objects
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if one changes, so will the other
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None of the above
AI Explanation
To answer this question, you need to understand how StringBuilder objects work.
StringBuilder objects in Java are mutable, which means their values can be changed. When you create a StringBuilder object and assign it a specific string, you can modify the content of that object without creating a new object.
Now, let's go through each option to understand why it is correct or incorrect:
Option A) They represent the same memory location - This option is incorrect. StringBuilder objects are separate objects that can have the same content but are stored in different memory locations.
Option B) They are two different objects - This option is correct. If two StringBuilder objects contain the same string, they are still considered as separate objects. They have their own memory locations and can be modified independently.
Option C) If one changes, so will the other - This option is incorrect. If you modify the content of one StringBuilder object, it will not affect the other StringBuilder object, even if they contain the same string.
Option D) None of the above - This option is incorrect. Option B is the correct answer because StringBuilder objects with the same string content are still separate objects.
Therefore, the correct answer is B) They are two different objects.
The proper way to convert a string to all lowercase is:
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String = string.ToLower(string);
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ToLower(string);
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string.ToLower();
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string.ToLower(string);