JavaScript closures and scopes this

General usage of closures and this

About JS function and closure of the article presumably everyone is familiar with, as the JS Core is one of the most powerful features, every time back to look at a look, there will be a different harvest and understanding, the classic meaning is nothing more than that.

• 1. Closures

1.1 First talk about the meaning of the closure in JS, closure (closure) of the main role in fact, three points:

• A. Accessing external variables
• B. Protecting local variables
• C. Automatic recovery and recycling

1.2 Definition of closures:

JavaScript closures and scopes this