The difference of exports and Module.exports in Nodejs detailed Introduction _ Basics

You must be very familiar with the exports object in the Nodejs module, and you can use it to create your module. For example: (assuming this is a rocker.js file)

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Exports.name = function () {
Console.log (' My name is Lemmy Kilmister ');
};

In another file you quote like this

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var rocker = require ('./rocker.js ');
Rocker.name (); ' My name is Lemmy Kilmister '

So what exactly is Module.exports? Is it legal?
In fact, Module.exports is the real interface, and exports is just one of its auxiliary tools. The final return to the call is module.exports rather than exports.

All exports collected properties and methods are assigned to Module.exports. Of course, there is a premise that the module.exports itself does not have any attributes or methods. If Module.exports already has some properties and methods, the information collected by exports will be ignored.

Modify Rocker.js as follows:

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Module.exports = ' Rock it! ';
Exports.name = function () {
Console.log (' My name is Lemmy Kilmister ');
};

Referencing the execution rocker.js again

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var rocker = require ('./rocker.js ');
Rocker.name (); Typeerror:object Rock It! Has no method ' name '

Error found: Object "Rock it!" No Name method
The rocker module ignores the exports collection's name method and returns a string "Rock it!". As it is, your module does not necessarily have to return "instantiated objects". Your module can be any legitimate JavaScript object--boolean, number, date, JSON, string, function, array, and so on.

Your module can be anything you set to it. If you do not explicitly set any properties and methods for Module.exports, then your module is exports set to Module.exports properties.

In the following example, your module is a class:

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Module.exports = function (name, age) {
THIS.name = name;
This.age = age;
This.about = function () {
Console.log (THIS.name + ' is ' + this.age + ' years old ');
};
};

You can apply it this way:

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var rocker = require ('./rocker.js ');
var r = new Rocker (' Ozzy ', 62);
R.about (); Ozzy is years old

In the following example, your module is an array:

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Module.exports = [' Lemmy Kilmister ', ' Ozzy Osbourne ', ' Ronnie James Dio ', ' Steven Tyler ', ' Mick Jagger '];

You can apply it this way:

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var rocker = require ('./rocker.js ');
Console.log (' Rockin in Heaven: ' + rocker[2]); Rockin in Heaven:ronnie James Dio

Now you understand that if you want your module to be a specific type, use Module.exports. If the module you want is a typical "instantiated object", use exports.

Adding attributes to Module.exports is similar to adding attributes to exports. For example:

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Module.exports.name = function () {
Console.log (' My name is Lemmy Kilmister ');
};

Again, exports is like this.

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Exports.name = function () {
Console.log (' My name is Lemmy Kilmister ');
};

Please note that these two results do not want to be the same. As mentioned earlier, Module.exports is a real interface, and exports is nothing more than its auxiliary tool. It is recommended to use exports export unless you intend to change from the original "instantiated object" to a type.