Rami Vemula

In this part of the tutorial, we carry on with the construction of MVP Pattern. First we start with the creation of View interfaces for the UserControls (which we created in PART II). Then we create the presenter classes, which will take the corresponding instances of views and then manipulate the view using Model classes (there by achieving code portability). Once we are done with the presenter classes, we implement the View interfaces in the codebehind of the UserControls. Finally we create a sample ASP.Net web page (typically webform), and use the UserControls for database transactions.

In this part of the tutorial – We first code for the CustomerService.cs by implementing ICustomerService.cs interface. We use LINQ queries to code database transactions. Then we create a host application (here it is a Console application) which operates the WCF service. Then we create a sample website for implementing MVP Pattern to access WCF. In the website, we implement some UserControls for fetching/updating/deleting records from the database.

First we create a database – ‘CustomersDB’ – with a table in it – ‘Customers’. This table Customers holds the basic data related to each and every customer. Then we create the entity model for this CustomersDB using ADO.Net Entity Framework. After that we create a WCF service with minimal end point configuration to access ServiceContracts which do basic database operations. Instead of coding the data access methods (of the class implementing ServiceContract) in traditional ADO.Net queries, we tend to use LINQ for the same. Once the service is ready, we host it using a Console App. With this we complete the backend of the article. Now we implement the MVP pattern for better separation of UI from its code with the help of presenter class. So we create an interface for both model and view and then implement them in their respective class. Finally we create a UI with some UserControls in it for adding/editing/deleting customers from the front end.

1) The code in this tutorial demos on how to raise an event of UsercControl which is on Parent page.
2) We got a UserControl (TestUserControl.ascx), which got a button in it. On Button click, we use a delegate to call an event from the parent page.
3) Even though personally I can’t vote to this approach of linking Page to its UserControl, but its worthy to know the procedure (as some situations may demand it).

1. It is sometimes required to make UserControls communicate between each other. So the following demo is used to show the same.
2. Even though there are advantages in communicating the Usercontrols, in some cases it increases the dependency between them which can hinder the robustness of the page.