Instance Analysis of Global Variables in nodejs

1.global

Similar to window in the client javascript running environment

module1.js:

module.exports={};
// The shameful use of global variables 
global.varA = "abc";

With regard to the global object, global can be omitted in actual use. It is the default root scope, which is equivalent to the window object in the web environment.

The global object has several useful properties:

console.log(__dirname);// Current path 
console.log(__filename);// Currently executing js File path 
//global.process  Gets the current Process Instances 

2.process

Obtain the current Node process information, which is generally used to obtain information such as environment variables

process.on('exit', function(code) {
 //  The following code will never be executed 
 setTimeout(function() {
  console.log(" The code does not execute ");
 }, 0);
 console.log(' The exit code is :', code);
});
console.log(" End of program execution ");

3.console

Input and output

main.js:

var c = require("./calculator");
console.log(global.varA);// Use global Object accesses to the " Global " Variable