CoomonJS modules provide a clean syntax for importing dependencies. This lesson will take a look at the basics of using CommonJS modules.
app.js
var dep = require(‘./dep‘); console.log(dep); // Exports a string back
dep.js
module.exports = "Exports a string back";
You can exports anything, such as an function:
app.js
var dep = require(‘./dep‘); console.log(dep()); // Export a function back
dep.js
module.exports = function() { return "Exports a function back"; }
Exprots multi-value:
app.js
var dep = require(‘./dep‘); console.log(dep.foo, dep.bar); //foo, bar
dep.js
module.exports = { foo: "foo", bar: "bar" }
Normally, you should do like this, using exprots object directly:
app.js
exports.foo = "foo";
exports.bar = "bar";
原文：http://www.cnblogs.com/Answer1215/p/4152377.html