Ejemplo n.º 1
0
        //----------
        static void Main(string[] args)
        {
            // here's what you need to observe in this program...
            // the process or creating an object from a class template
            // is called "instantiation" (pronounced "instanciation").
            // instantiation is a four step process:
            // 1) the new operator allocates a block of memory to hold
            //    a new object.
            // 2) the new operator invokes the specified constructor
            //    method to initialize the object's block of memory...
            //    instance variables (fields) are set up and initial
            //    values are moved into them.
            // 3) a constructor method is unique in that it does not
            //    return a value (no return value, not even "void").
            //    this is so that the new operator can return a reference
            //    pointer that points indirectly to the newly-created
            //    object. the reference pointer is not really a memory
            //    address, but more of a way to get to that memory address.
            // 4) the assignment operator "shoves" the reference pointer
            //    into a typed variable that points to the object.

            // instantiate box 1 & initialize it
            Box Box1 = new Box(6.0, 7.0, 5.0);

            // instantiate box 2 & initialize it
            Box Box2 = new Box(12.0, 13.0, 10.0);

            // dump out the calculated volumes of Box 1 & Box 2:
            // encapsulation is a wonderful concept that we will be
            // visiting again and again as we do object-oriented
            // programming. the important idea is that we should
            // move as much of the code that uses the Box data into
            // Box class methods as possible.
            //
            // for example, rather than accessing the Box data in this
            // function to calculate the volume of the various boxes,
            // whereever it is needed, it is better to create a single
            // volume() method in the Box class that can be invoked
            // wherever it is needed.  (duplicated code is rarely a
            // good idea because it is too easy to proliferate
            // programming errors.)

            Console.WriteLine("Volume of Box1 : {0}", Box1.volume());
            Console.WriteLine("Volume of Box2 : {0}", Box2.volume());

            Console.Write("Press Enter to continue...");
            Console.ReadKey();
        }