ASP .Net MVC

Introduction to ASP .Net MVC

MVC (Model View Controller) is a software architecture pattern that is used for separation of concern where application development in ASP .NET, JAVA, PHP, etc are using it to keep cleaner codes. One area of UI concern should not depend on business logic or data access and vice versa.

From above statement, you come up with several questions about "what is separation of concern?", "What is cleaner codes?" and several other whats. 

I break down those into details with ASP .NET and you will know what MVC is and how it works by the end of this article.

What is Separation of Concern?

Before MVC, ASP .NET Web Form uses events driven approach programming. For example, when you drag and drop a text box and double click on it, it has built-in event codes. Using two or a few items like textbox or dropdownlist is ignorable. It seems easy to work, but it comes with so much disadvantages. But when you are developing large-scale application, it becomes complex to understand how all the codes work behind the scene. If any changes need to make, it becomes hectic work to complete and there is no traceability of codes.

For those reasons, MVC comes into picture. In a typical application of MVC, we can break down into three layers for application development as you may already expect:  Model, View and Controller

Model represents how data is structured, stored and access to database. This layer is interchangeably called Data Access Layer or Business Logic Layer.

View represents what user see on the screen or View takes inputs from users to request what they want to see. The View layer is also called Display Layer. In View, you do not have option to click on toolboxes where Web Form usually takes you into code-behind cs file. This gives developers full control over how UI should be designed and layout. View can be created strongly-type from Model Layer, which expert developers recommend to do.

Controller represents as input control manager who respond and redirect View's requests (user inputs) to the appropriate Model. This layer take in what user are requesting and will either pass to Model Layer to retrieve data or calculate and process the logic inside controller and pass back to View to display the result.

Here is MVC flow diagram.

MVC also helps to separate frontend and backend developers. While frontend developers are working on UI, backend developers can work on the business logic and data access logic at the same time.

Later section, I will discuss about how MVC is used with demo.