Before we conclude, it is important to take a brief look at object oriented program. In order to work with the class libraries of the .net framework, it is a good idea to have a solid understanding of objects oriented programming. If you feel that you already have this knowledge, feel free to skip this section.
This section is not going to provide a deep dive into the tenants of object oriented programming, but instead, to provide a high level understanding of the concepts. We will simply take a brief moment to understand the vocabulary of object oriented design. Let us begin with the scenario.
Let us say you are the architect of a large project. You get a requirement from your costumer that says “I like an application that enables my employees to log in and view order data”. They should be able to see the details for an order such as when the order is placed, who placed it, the product ordered and the quantity of the product that they ordered. My employee should also be able to view shipment information such as when the order was shipped.
So, in order to understand what this business requirement means in object oriented vocabulary, we will need to examine the requirement a bit more closely. So the costumers said that they like an application that enables their employees to log in and view order data. So, let us take a look at the first sentence. “I would like an application that enables my employees to log in and view ordered data”. So look for the nouns, application, employees, order, these are good candidates to be a class and it is a good rule of thumb to identify your classes when using object oriented programming. Now, let us take a look at where the method is. A method works base similar to a verb. It is something that occurs to a noun.
So, let us look at that same sentence. “I would like an application that enables my employees to log in and view order data”. Log in and view, these are both verbs that will occur to one of the nouns. An employee can log in. So therefore, a good candidate for a method for the employee object would be the method log in. likewise for an order, a good method would be view.
Now, let us understand properties. Properties are attributes of the class and they work much like adjectives. So think about the employee object. If I have an employee, what are some attributes that I wish to capture about an employee? I might want to capture first name, last name, maybe I want to capture social security number. These will all be properties of my employee object.
And lastly, we have events. Events are occurrences that happen to a class. This is where I get a little bit obstructed. Events tend to be system occurrences. For example, you may want to capture the event after an employee record is deleted, so you can send a message to a human resources system. User interface interactions are also events such as the click of a button. In that case, an event is capturing a reaction of the user.
Hopefully, by having a brief look of object oriented programming, you will be able to better understand the .net framework 2.0.
