First, let’s take a look at the official documentation

module.exports

A reference to the current module, see the section about the module object. In particular, module.exports is used for defining what a module exports and makes available through require().

The module object is a reference to the current module object. Module. exports is created by the Module system to represent the content to be exported from that module

exports

  • A reference to the module.exports that is shorter to type.

  • The exports variable is available within a module’s file-level scope, and is assigned the value of module.exports before the module is evaluated.

  • It allows a shortcut, so that module.exports.f = ... can be written more succinctly as exports.f = .... However, be aware that like any variable, if a new value is assigned to exports, it is no longer bound to module.exports:

    module.exports.hello = true;      // Exported from require of module
exports = { hello: false };       // Not exported, only available in the module
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Exports is a shorthand for module.exports, which is scoped at the file level, just like module scoped.

Exports and module.exports refer to the same reference by default (starting with {}), that is, exports is a reference to module.exports

console.log(exports, module.exports, exports === module.exports);
//            {}           {}                 true    
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. That is modify the exports or the module exports any value will lead to another value of synchronization, which means you can use any way to export the contents of the module, the require (module) of content is {2} a:

module.exports.a = 2;
console.log(exports, module.exports, exports === module.exports);
//           {a: 2}       {a: 2}             true

exports.a = 2;
console.log(exports, module.exports, exports === module.exports);
//           {a: 2}       {a: 2}             true
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At this moment, the fine line

If you modify module.exports and exports at the same time, what does require(module) import?

exports.a = 2;
module.exports.a = 3;
console.log(exports, module.exports, exports === module.exports);
//           {a: 3}       {a: 3}              true
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  • Exports === module.exports = true

  • Because the value changed at this point only changes the base datatype, not the reference to the value, the values of these two people are unchanged

  • After modifying the reference to the value at the same time, let’s see what happens after require(module).

  • exports.a = 2; module.exports = { b: 3 }; console.log(exports, module.exports, exports === module.exports); {a: 2} {b:3}} {b:3}Copy the code

Description: Whether exported from exports or module.exports, the module content accepted by Requeire is exported from the Module. exports object.

Then there is the way they export a little bit differently. Exports only support use. The syntax exposes internal variables, which is supported by module.export. The syntax supports copying an object directly

It’s quite a mess, so let’s sum it up:

With:

  • Both can expose modules outwards

  • References to both values point to the same place

Vision:

  • Require only accepts variables exposed by module.exports

  • Exports only supports. Syntax, Module. exports supports. Syntax and direct assignment object forms

Shout ~ finished, happy heart