Calling a function from another JS file And Node Directory Structure

Question

MessageHandler.HandleMessage(message);The question might seem to be 2 parts, but I think there might be overlap between them.

I'm making a very simple Node application where I could, theoretically, put all my functions in the same JS file. However like C# (where you could theoretically put all your classes on the same page) this is going to get cluttered very quickly and is likely considered bad practice.

I have the basic node generation structure (as shown in the sublime explorer):

But I'm not sure where is the standard place for me to start putting my JS.

Looping back to the first part of my question I have this very simple code.

    //file: MyNode.js
    const MessageHandler = require('MessageHandler.js');
    var message = "Hello world!";
    MessageHandler.HandleMessage(message);

And:

    //file: MessageHandler.js
    function HandleMessage(message)
    {
        Console.log('Message is this: ' + message);

    }

They are in the same file directory but during execution I get a HandleMessage is not a function. type error. Is there a structuring or scope problem that I'm not seeing?

Answer 1

Actually, your code is correct but needs little addition, you need to export the required function to expose or to use in another js file.

// a.js
anyFun() {
// body
}

you can use module.exports = anyFun;

//b.js

let a = require('./a')

a(); 

    In your case:

    //file: MessageHandler.js
       module.exports.HandleMessage = function HandleMessage(message)
    {
        console.log('Message is this: ' + message);

    }

   //file: MyNode.js

  let demo = require("./MessageHandler");

  demo.HandleMessage('hello');