module export in node js

Module Export in Node.js

In Node.js, the module.exports object is used to export functions, objects, or values from a module to make them accessible to other modules. Here are the steps involved in using module.exports:

  1. Define the module: Create a JavaScript file that contains the code you want to export. This file is known as a module.

  2. Declare the exports: Inside the module, use the module.exports object to declare the functions, objects, or values that you want to make available to other modules. You can assign a function, an object, or a value directly to module.exports.

Example: ```javascript // square.js module.exports.area = function (width) { return width * width; };

module.exports.perimeter = function (width) { return 4 * width; }; ```

In the above example, the area and perimeter functions are assigned to the module.exports object.

  1. Import the module: In another module, use the require() function to import the module that exports the desired functions, objects, or values.

Example: ```javascript // main.js const square = require("./square");

console.log(square.area(5)); // Output: 25 console.log(square.perimeter(5)); // Output: 20 ```

In the above example, the require() function is used to import the square.js module. The exported functions area and perimeter can then be accessed using the square object.

That's it! By following these steps, you can export and import functions, objects, or values between modules in Node.js using module.exports and require().