What is an MVC framework and why is it necessary/u

问题:

I know that an MVC framework allows you to separate business logic, data base access and presentation, but why do we need a framework to do this.

Can't we just keep our classes separated, perhaps using different packages/folders for the model, view and controller classes?

回答1:

In my opinion the thing you are talking about is the MVC pattern and not a specific framework. Of course you can go and keep all your classes within one project and still use the MVC pattern, as you have all your UI code in the views, the logic in the controllers, ...

A MVC framework on the other hand makes it easier for you to use this pattern. It may provide some base classes for controllers and a mechanism for the communication between view and controller.

I don't know if you are familiar with ASP.NET MVC. The framework itself is very small, but it helps you developing an application with the MVC pattern, as you don't have do think about the previously decribed areas...

Hope this helps

回答2:

An MVC framework is a framework written to split up the the business logic, database access and presentation.

This is very useful in most web applications, and now lately into software/desktop applications.

This is due to the fact that following the MVC model, your code will be much clearer, cleaner and you keep your application DRY (Do not Repeat Yourself).

You can write your own classes and separate them into Model, View and Control. But again, you will need a framework to help you in accomplishing certain tasks. Like a List control in ASP.NET, or PHP framework being able to help you translate text between languages and so on. (Oh why reinvent the wheel?!)

回答3:

MVC and framework is a different thing. MVC is just an architectural pattern, which can be applied with any project, with or without framework.

So you don't need a framework to do this. You can separate them by yourself. :)

回答4:

MVC stands for “MODEL” “VIEW” “CONTROLLER”. ASP.NET MVC is an architecture to develop ASP.NET web applications in a different manner than the traditional ASP.NET web development. Web applications developed with ASP.NET MVC are even more SEO (Search Engine) friendly. Developing ASP.NET MVC application requires Microsoft .NET Framework 3.5 or higher.

Model:

• MVC model is basically a C# or VB.NET class.
• A model is accessible by both controller and view.
• A model can be used to pass data from Controller to view.
• A view can use model to display data in page.

View:

• View is an ASPX page without having a code behind file.
• All page specific HTML generation and formatting can be done inside view.
• One can use Inline code (server tags ) to develop dynamic pages.
• A request to view (ASPX page) can be made only from a controller’s action method

Controller:

• Controller is basically a C# or VB.NET class which inherits system.mvc.controller.
• Controller is a heart of the entire MVC architecture.
• Inside Controller’s class action methods can be implemented which are responsible for responding to browser OR calling views.
• Controller can access and use model class to pass data to views
• Controller uses ViewData to pass any data to view.

回答5:

MVC is a code organization architecture style to organize your code-logic in a meaningful way for web applications. As a programmer I have almost puked when I have inherited other people's code when their code logic is all over the place and following their web application code turns into following a rabbit down the gutter hole. Why MVC? hmm.. well why should I use a filing cabinet or folders to organize my plethora of paper and not just have my papers stashed in a large pile and have others figure how they connect to each other. It increases code readability. With MVC it becomes very easy to follow code logic since you are following standard structure for a web application. Business logic is separated out from UI. Easier to delegate work decouple work on a project.

回答6:

You can of course approach it yourself by segregating your classes. A framework supplies common scaffolding that you wouldn't have to build yourself. But it will also impose some structure on your code. You'll have to evaluate whether the framework helps more than it hurts.

回答7:

You are correct, there are strategies that you can implement to help with separation of concerns without using MVC.

Microsoft's ASP.NET MVC framework is one strategy that can be employed, and that is what I think you are asking about. This MVC framework makes such separation of concerns easy.

The other major advantage of MVC is testability - (depends on whether you believe in unit testing - I do).
The MVC framework ensures that all orchestration logic is on your controllers and through the FormControls collection allows full unit testing of all aspects of your application except for how it is presented.

As the MS MVC framework encourages adherence to common rules and structure of the application which should lead to greater maintainability.

The major downside of MVC is the code-in-front code weaving required for presentation, but this can be easily overcome.

回答8:

Perhaps this is just a linguistic thing. I've seen "frameworks" referring to themselves as a DSL -- Domain Specific Language.

And you don't need a framework But here's something to consider: You already know for a web app you're going to want to do a few common things... route URLs, render pages, etc. Why re-write it all? For other problem domains you'll have generic things to do as well.

回答9:

Hai Friends There are somemany types of architecture frame work has been there,firstly i know 2tier and 3 tier frame work ,the 3 tier and mvc ,entity framework are same but in different name's,so study a good background in any one architecture there fore if you went to any multinational companies ,you can easly score/highlight to your carrer.

Model View Controller or MVC as it is popularly called, is a software design
pattern for developing web applications. A Model View Controller pattern is made 
up of the following three parts:

**Model** - The lowest level of the pattern which is responsible for maintaining data.

**View** - This is responsible for displaying all or a portion of the data to the user.

**Controller** - Software Code that controls the interactions between the Model and View