Closure self-invocation of functions in JavaScript

Words don't say much, directly on the code

Define a variable Outerparam, and then use a closure function to initialize the variable.

var outerparam = (function testclosure (param) {//param is a formal parameter, used inside the function

 "a";                            Begins the operation of the parameter,            encapsulating "b";                           return   ///Final return parameter, which is to return the encapsulated data to the Outerparam

The last variable Outerparam is structured as follows: It can be called externally

Closure self-invocation of functions in JavaScript