C# Test 6

Question 2: What will be the output of the following program?

public static void Main()
{
	Action DoSomething = () => Console.WriteLine("Hello!");
       
    DoSomething();
}

• Blank output
• Hello!
• Compile-timer error
• Runtime error

Question 3: When will be T will be replaced with the actual type in the following program?

class ValueProcessor<T>
{
    // Implementation 
}

• Run time
• Compile-time
• Debugging time
• Never

Question 4: What will be the output of the following program?

class Program
{
    static void Main(string[] args)
    {
        DataProcessor<string> p2 = new DataProcessor<string>();
        p2.Process(100);
    }

}


class Processor<T>
{
    public void Process(T value)
    {
        Console.Write(value.GetType().Name);
    }
}

class DataProcessor<U> : Processor<int>
{

}

• Compile-time error
• Runtime error
• Int32
• String

Question 5: Which of the following generic constraints restricts the generic type parameter to an object of the class that implements IEnumerable interface?

• class Processor<T> where T: class:IEnumerable
• class Processor<T> T: interface IEnumerable
• class Processor<T> where T: IEnumerable
• class Processor<T> where T:new()

Question 6: What will be the output of the following code?

ValueTuple person = (1, "Tom");
Console.Write(person.Item2);

• 1
• Tom
• Compile-timer error
• Runtime error

Question 7: Which of the following types can implement interfaces?

• Class
• Struct
• Enum
• Event

Question 8: Can we declare a protected member in an interface?

• Yes
• No

Question 9: Which of the following types can participate in inheritance in C#?

• Class, Struct, Interface
• Class, Enum, Interface
• Class, Object, Delegate
• All the reference types

Question 10: What will be the output of the following program?

class Person
{
    public void Introduction(){ 
        Console.WriteLine("I am a person.");
    }

    public string Introduction(){ 
        return "I am a person.";
    }
}

• Program will compile and run successfully.
• Program will compile successfully but will throw an exception at runtime.
• Program will give a compile-time error.
• Program will give a compile-time warning but will run successfully.

Question 11: What does the following code do?

File.WriteAllText(@"C:\MyFile.txt", "This is file content.");

• Creates a new file and writes the text to the MyFile.txt
• Creates a new file and writes the text to the MyFile.txt. If the file already exists, then throw an exception.
• Creates a new file and writes the text to the MyFile.txt. If the file already exists, then overwrite the text to the file.
• Opens file for reading or write operation.

Question 12: What will be the output of Console.Write(sizeof(int));?

• 0
• 4
• Compile-time error
• Runtime error

Question 13: What is the difference between interface and abstract class?

• Interface can only have method declaration whereas abstract class can have method implementation.
• Interface can have method implementation whereas abstract class can have method declarations as well as implementation.
• Multiple interfaces can be implemented whereas multiple abstract classes cannot
• None of the above

Question 14: How to restrict a class to be a base class?

• Use sealed keyword
• Use generic class
• Use virtual keyword
• Use abstract keyword

Question 15: How to access members of the base class from within a derived class?

• Using base keyword
• Using this keyword
• Using : operator
• None of the above