Model View Controller (MVC) Interview Preparation Guide

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Model–View–Controller (MVC) is a design pattern in which "the user input, the modeling of the external world, and the visual feedback to the user are explicitly separated and handled by three types of object." The model consists of data and business rules, and the controller mediates the communication between the model and the user. A view can be any visual element such as a printout or a web page. Multiple views of the same data are possible, such as a pie chart for management and a spreadsheet for accountants.

I would use refs config to set a reference on the Application/Controllers

There are no requirements.. if you want to use a Viewport you can! If you want to render components into divs... you can do that aswell.

Search on Global Guideline I hope you will get answer

What do you mean open? explain more..

What MVC are you using? Views are for presenting the data from a Model. Model is just a representation of data. Controllers should be what controls you app like telling your view to display this model.

1. M - Model
2. V - View
3. C - Controller

System.Web.Mvc

Yes, it is possible to combine ASP.NET webforms and ASP.MVC and develop a single web application.

Model: Model represents the application data domain. In short the applications business logic is contained with in the model.

View: Views represent the user interface, with which the end users interact. In short the all the user interface logic is contained with in the UI.

Controller: Controller is the component that responds to user actions. Based on the user actions, the respective controller, work with the model, and selects a view to render that displays the user interface. The user input logic is contained with in the controller.

It is difficult to unit test UI with webforms, where views in mvc can be very easily unit tested.

1. Extensive support for TDD. With asp.net MVC, views can also be very easily unit tested.
2. Complex applications can be easily managed
3. Seperation of concerns. Different aspects of the application can be divided into Model, View and Controller.
4. ASP.NET MVC views are light weight, as they donot use viewstate.

Yes, all the features in an asp.net MVC application are interface based and hence mocking is much easier. So, we don't have to run the controllers in an ASP.NET process for unit testing.

Yes, put the view into the shared folder. This will automatically make the view available across multiple controllers.

The controller responds to user interactions, with the application, by selecting the action method to execute and alse selecting the view to render.

In Application_Start event in Global.asax

The following are just a few return types of a controller action method. In general an action method can return an instance of a any class that derives from ActionResult class.
1. ViewResult
2. JavaScriptResult
3. RedirectResult
4. ContentResult
5. JsonResult

In general, all public methods of a controller class are treated as action methods. If you want prevent this default behaviour, just decorate the public method with NonActionAttribute.

ASP.NET MVC uses ASP.NET routing, to map incoming browser requests to controller action methods. ASP.NET Routing makes use of route table. Route table is created when your web application first starts. The route table is present in the Global.asax file.

1st Segment - Controller Name
2nd Segment - Action Method Name
3rd Segment - Parameter that is passed to the action method

1. Web.Config File : ASP.NET routing has to be enabled here.
2. Global.asax File : The Route table is created in the application Start event handler, of the Global.asax file.

In an ASP.NET web application that does not make use of routing, an incoming browser request should map to a physical file. If the file does not exist, we get page not found error.

An ASP.NET web application that does make use of routing, makes use of URLs that do not have to map to specific files in a Web site. Because the URL does not have to map to a file, you can use URLs that are descriptive of the user's action and therefore are more easily understood by users.

1. URL Pattern - You can include placeholders in a URL pattern so that variable data can be passed to the request handler without requiring a query string.
2. Handler - The handler can be a physical file such as an .aspx file or a controller class.
3. Name for the Route - Name is optional.

{controller}{action}/{id}
No, the above definition is not a valid route definition, because there is no literal value or delimiter between the placeholders. Therefore, routing cannot determine where to separate the value for the controller placeholder from the value for the action placeholder.

{resource}.axd/{*pathInfo}
This route definition, prevent requests for the Web resource files such as WebResource.axd or ScriptResource.axd from being passed to a controller.