JavaScript modularity and namespaces

Generally speaking, the module is a separate JS file. A module file can contain a class definition, a set of related classes, a utility library, or some code to execute. The goal of modularity is to support large-scale program development, to handle the assembly of code in a decentralized source, and to allow code to run correctly, even if it contains unnecessary module code, and can execute code correctly.

by defining the module within a function, the defined variables and functions belong to the function's local variables and are not visible outside the function. In fact, this function scope can be used as a module namespace (module function)

Once the module code is encapsulated in a function, some methods are required to export the public API to invoke them outside of the module functions. There are several ways to export a common API:

first create a namespace

Create a global variable to hold school-related modules
var School; Create a school namespace
if (!school) school = {};

1. Using the constructor function

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2. Call through the keyword new
Another similar technique is to call a module function as a constructor, via new. Assign them (public API) to the This property to export them

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3. namespace objects are defined

as an alternative, if a global namespace object has been defined, the properties of that object can be set directly through the module function.

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The way to export the public API has been finished.

This article is from the "Add Language" blog, please make sure to keep this source http://yuguotianqing.blog.51cto.com/9292883/1547559

JavaScript modularity and namespaces