How do I use callback functions in JavaScript?

How do I use callback functions in JavaScript?

Callback functions are functions passed as arguments to other functions. They are executed after a certain event or action.

Can you give me an example of a callback function?

Sure! Here's a simple example:

function greet(name, callback) {
    console.log('Hello ' + name);
    callback();
}

function sayGoodbye() {
    console.log('Goodbye!');
}

greet('Alice', sayGoodbye);

In this example, sayGoodbye is a callback function.

What if I want to use a callback with asynchronous code?

Great question! In asynchronous code, callbacks are often used to handle operations like API requests. For example:

setTimeout(function() {
    console.log('This runs after 2 seconds');
}, 2000);

Here, the function inside setTimeout is a callback that runs after a delay.

Are there any drawbacks to using callback functions?

Yes, one common issue is 'callback hell', where callbacks are nested within callbacks, making code hard to read. Promises and async/await can help mitigate this.