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This article shows you how to understand the Web front-end framework and class library thinking, the content is concise and easy to understand, can definitely brighten your eyes, through the detailed introduction of this article, I hope you can get something.

Of course, it is not to belittle the frame, but there is a feeling of killing a chicken with a knife. Web technology exists for business, and apart from that it makes no sense, so is the framework. In the technology selection and architecture design, away from the reality of the network station business development, blindly pursue fashionable new technology, may be counterproductive, the website development into the rugged path. It's like a small e-commerce site with an average daily pv of only a few hundred, shouting "this is how it works," and then building a cluster of application servers, using distributed file systems and distributed database systems. Wait for a bunch of Barabara to deal with high concurrency, massive data access means. I mean, does it make sense?

Misunderstandings of Front-end Framework

The value of the website lies in what value it can provide to users, what the site can do, not how it is done, so it is not worth the loss to pursue the architectural framework of the website when the site is still very young. Similarly, if the front-end framework is a simple page-based product, the application only relies on the server to generate Web pages and views, and only needs to use some simple Javascript or JQuery to make the application more interactive, then a JQuery front-end class library is fine, there is really no need to use some high-end framework.

Of course, frameworks are really useful, and the point is that we need to know when and which frameworks to use. The experience and successful model of large projects in large companies are important and worth learning from, but we should not follow them blindly. Only by deeply understanding the front-end framework and knowing when and what framework should be used to solve what problems, can we have a clear target and get to the point.

The difference between Front-end Framework and Front-end Class Library

Before using a framework, I think it's important to understand the difference between a class library (such as JQuery) and a framework (such as angularJS).

To put it simply, the class library solves the problem of code or module-level reuse or the encapsulation of complexity, such as encapsulating a functional module to solve complex problems into a function and providing a simple interface. Library is a tool, it provides a lot of encapsulated methods, use or not depends on us, even if we use it will not affect our code structure.

On the other hand, the framework is more about the reuse of the pattern level and the standardization of program organization. The pattern here refers to, such as MVC, in order to decouple M and V, the complex coupling relationship is transferred from the frequently changing business code to the internal digestion of the infrequent framework. Is to provide a set of solutions for a field to improve development efficiency, if we choose to use a framework, we should follow the rules stipulated in the framework.

The main difference between the two is that JQuery is centered on DOM operations, the framework, to be exact, the MVC framework, is model-centric, while DOM operations are additional. Therefore, the ultimate goal of taking the model as the center is to bring a whole set of workflow changes, so that the background engineer can write the front-end model code, connect the background and the front-end, the interaction designer handles the interaction between UI and the model, and the UI designer can focus on and barrier-free the HTML source code and submit them to the interaction engineer in the form of interface template. This set of cooperation mechanisms can greatly improve the efficiency of development. The front-end tasks are better decoupled by using the MVC framework.

Front-end MVC framework idea

We know that the traditional MVC mode divides an application into model layer (model), view layer (view) and control layer (controller). They play different roles and accomplish different tasks in the application system.

Model: the data model, which is used to wrap or process data related to the business logic of the application, and the model can access the data directly.

View: the view is used to display data purposefully, and there is generally no procedural logic in the view. In order to implement the * * function on the view, the view needs to access the data model it monitors.

Controller: the controller regulates the connection between the model and the view. It controls the flow of the application, handles and responds to events that include not only the user's behavior but also changes in the data model. By capturing user events, the model layer is notified to make corresponding updates, and at the same time, the updates and changes of the model layer are notified to the view, which makes the view change accordingly. So the controller ensures the consistency of the view and the model.

So the performance in the front end. Responsibilities of the various parts of the front-end MVC:

My understanding of the front-end View is that the parts directly related to the elements on the page belong to View. This includes html,CSS and some JS that directly control the elements of the page. You can get the data from Model and display it on the page. On the other hand, all the changes and requests for data are handed over to Controller.

What about Controller? As a glue between Model and View, Controller forwards requests for View to the appropriate Model and updates View if necessary. The Controller itself can also act as an observer of the Model, obtaining changes to the Model. As Controller itself, there should be no code that involves page elements.

* talk about Model. Communication with the backend, AJAX requests and data processing all belong to Model. Model itself does not know who is View and who is Controller. It provides only a few methods for View and Controller to call and notifies its observer View or Controller of the change. Obviously, the Model is also decoupled from the page elements.

Although there are many differences between frameworks based on the MVC model, in general, Model is responsible for storing the data needed by vier and data processing logic, such as read and write, update, delete, validation, transformation, etc. View is responsible for receiving and displaying the data provided by Model and receiving the input of the user, and responds to the event, and feedback the update back to the user in time after the Model update. Controller handles business logic and event logic.

Know yourself and the enemy, and prescribe the right medicine to the case.

Today, the front-end framework and class libraries are becoming more and more abundant. Choosing the right framework or class library is particularly important. I don't think it's necessary to follow the trend blindly. When I see any frame fire, I run to eat it for a week, and then forget all about it a few months later because I don't need it in the project work.

So I think it is important to lay a solid foundation, the key point is to understand the role of various class libraries and frameworks, what kind of framework is used to solve what problems, and then when the project needs to study API is the best policy.

We should be aware of the limitations of the application of MVC in front-end development. Simple projects may become more complex if they use the MVC framework. Of course, with the increasing complexity of the Web front-end and the continuous development of the front-end MVC framework, I believe that in the future complex application software products, the MVC framework will certainly bring efficiency leaps to the front-end work.

The above content is how to understand the Web front-end framework and class library thinking, have you learned the knowledge or skills? If you want to learn more skills or enrich your knowledge reserve, you are welcome to follow the industry information channel.

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