Shulou(Shulou.com)06/02 Report--

This article introduces the knowledge of "how to write your own JavaScript framework". In the operation of actual cases, many people will encounter such a dilemma, so let the editor lead you to learn how to deal with these situations. I hope you can read it carefully and be able to achieve something!

1. Definition and loading of modules

1.1 definition of the module

If a framework wants to support larger applications, it must first consider how to do modularization. With the kernel and module loading system, the peripheral modules can be added one by one. Different JavaScript frameworks have different ways to achieve modularization, so let's choose a more elegant way to explain it.

First of all, let me ask you a question: what is the purpose of our modular system? If you find this question difficult to answer, you can consider it from the negative side: if you do not do module system, what are the disadvantages?

We have experienced a relatively extensive and chaotic front-end development phase, the page is full of global variables, global functions. At that time, to reuse js files, you put some js functions in one file and have multiple pages refer to them.

Considering that a page can refer to multiple such js, these js do not know what is written in each other, it is easy to cause naming conflicts, and when there is such a conflict, there is no place to prompt. So we have to have a way to better separate the scope.

JavaScript is a strange language, where is it? there are no package and class in its current version, and if there is, we don't have to think about modularization ourselves. So what does it use to isolate its scope?

In many traditional high-level languages, the scope of variables is bounded by curly braces, and the scope of variables defined in {} will not be passed out, but this is not the case with our JavaScript adult. His boundary is function. So in our code, I can still type a value:

For (var item0; I

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