javascript: call function declared in a different .js file?

Question

I am writing some logic in fileB.js that needs to call another function declared in fileA.js. fileA.js declares a function called abc(). How can I call abc() from fileB.js.

Both fileA and fileB are in the same directory.

Thank you

Ps. I am not using this with HTML. I am just running it locally as part of another project I am working on. I am now using node to run it from terminal. But I am not using anything else in these two files. I just have a bunch of really simple functions. No node.js modules or anything...

Use Requirejs, it supports multiple environments and doesn't require a browser. — Kyle Needham
– Kyle Needham, Commented Oct 25, 2014 at 19:12

Jonathan Lonowski · Accepted Answer · 2014-10-25 19:37:45Z

2

Node.js isolates each file as a module, giving each their own local scope to define essentially "private" functions and vars.

With this isolation, fileA will need to export abc in order to share it with other files/modules:

function abc() {
    // ...
}

exports.abc = abc;

Then, fileB can require() fileA with a relative path (. referring to the current directory) and use its exported function:

var a = require('./fileA');

a.abc();

edited Oct 25, 2014 at 19:37

answered Oct 25, 2014 at 19:26

Jonathan Lonowski

124k35 gold badges203 silver badges202 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

zumzum Over a year ago

I am marking this as the correct not because I know the other ones do not work. I marked it as the answer because this worked for me and it seemed the most straight forward to implement at first look. Thank you.

Kuba Jagoda · Accepted Answer · 2014-10-25 19:23:10Z

1

If you are using node, then in fileA:

module.exports = { abc: abc } //assuming that abc holds a reference to your function, declared somewhere above

Then, in fileB you require fileA and use what you exported:

var fileA = require('./fileA.js');
fileA.abc();

answered Oct 25, 2014 at 19:23

Kuba Jagoda

5,6172 gold badges21 silver badges22 bronze badges

Comments

SquareFeet · Accepted Answer · 2014-10-25 19:25:44Z

Since you're running it in NodeJS, I'd suggest doing the following at the top of fileB.js:

var fileA = require( './fileA.js' );

However, in order for this to work, the functions you want to use in fileB.js should be exported from fileA.js. To do this, lets assume that the function abc() is what you want to access:

// In fileA.js:
function abc() {
    // ... do something ...
}

module.exports = abc;

If you want multiple functions/variables/objects available to fileB.js, you can export them all as one object:

// In fileA.js
function abc() {
    // ... do something here ...
}

var myObject = {
    propOne: 'foo',
    propTwo: 'bar
};

module.exports = {
    abc: abc,
    myObject: myObject
};

Then, within fileB.js:

// Import the fileA object you just created.
var fileA = require( './fileA.js' );

// Save references to abc and myObject
var myObject = fileA.myObject,
    abc = fileA.abc;

void · Accepted Answer · 2014-10-25 19:09:25Z

0

Just include both the JS files in the HTML and then simply call them any function anywhere, it will work.

answered Oct 25, 2014 at 19:09

void

36.8k10 gold badges72 silver badges111 bronze badges

5 Comments

zumzum Over a year ago

I am not using the JavaScript in an HTML page. I'm just running it locally for other stuff I'm working on

Patrick Evans Over a year ago

What do you mean you are running it locally?

zumzum Over a year ago

I'm running it from terminal.

D-side Over a year ago

@zumzum be more specific please. There are many ways to run JS from terminal.

zumzum Over a year ago

I am using node... "node fileB.js"

Collectives™ on Stack Overflow

javascript: call function declared in a different .js file?

4 Answers 4

1 Comment

Comments

Comments

5 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

1 Comment

Comments

Comments

5 Comments

Your Answer

Sign up or log in

Post as a guest

Related