Quiz 2 [Object-Oriented Programming]

A(n) _______ is a type that references a method.

A class that does not provide a complete implementation must be declared with the keyword _________.

You are writing a code to handel events in your protram. You define a delegate named RectangleHandler like this:

public delegate void RectangleHandler(Rectangle rect);

you also create a variable of the RectangleHandler type as follows:

RectangleHandler handler;

Later in the program, you need to add a method named DisplayArea to the methodinvocation list of the handler variable. The signature of the DisplayArea method matches the signature of the RectangleHandler method. Any code that you write should not affect any existing event-handling code. Given this restriction, which of the following codes should you write?

A(n) _______ is a blueprint of an object.

You are writing code for a class named Product. You need to make sure that the data members of the class are initialized to their correct values as soon as you create an object of the Product class. The initialization code should be always executed. What should you do?

You want to restrict the access for a method to the containing class or to a class that is derived from the containing class. Which access modifier should you use for this method?

The _______ keyword refers to the current instance of a class.

You can use ______ to group related classes in order to reduce name collisions.

You defined a class AdvMath that defines advanced mathematical functionality. You plan to make classes that are derived from AdvMath. You do not want the functionality of AdvMath class to be inherited into derived classes. What keyword should you use to define the AdvMath class?

You are creating a new class named Circle. You write the following code:

class Circle: IComparable
{

public double Radius{ get; set; }

public double GetArea()
{

return Radius*Radius*3.14159

}

public int CompareTo(object obj)
{

// some code will go here...

}

}

Which of the following class elements should you use to define the behavior of a class?

You can use the _____ keyword to declare a member that belongs to the class itself rather than to a specific object.

You can use the ______ operator to check whether it is legal to cast one type to another type.

INCOMPLETE

The Draw() method in the Square class should provide new functionality but also hide the Polygon class implementation of the Draw() method. Which line of code would accomplish this?

INCOMPLETE

You need to provide query functionality to several of your classes. Each class's algorithm for the query will likely be different. Also, not all the classes have an "is-a" relationship with each other. How should you support this functionality?

INCOMPLETE

You are writn code for a new method named Process:

void Process (object o)
{
//code goes here...
}

The code received a parameter of type object. You need to cast this object into the type Rectangle. At times, the value of o that is passed to the method might not be a valid Rectangle value. You need to make sure that the code does not generate any System.InvalidCastExpection errors while doing the conversion. Which of the following lines of code should you use inside the Process method to accomplish this goal?

INCOMPLETE

Classes that want to support comparison must implement the IComparable interface and then provide a body for the _______ method.

INCOMPLETE

In a class, you defined a method called Render. This method provides functionality to render bitmap files on a the screen. You would like the derived classes to supersede this functionality to support the rendering of additional image formats. You also want the Render method of the derived classes to be executed even if a derived class is cast as the base class. Which keyword should you use with the definition of the Render method in the base class?