A callback function is a function that is passed as an argument to another function. The callback function is executed after the outer function has finished executing. Callback functions are useful for developing asynchronous JavaScript code.
Here is an example of a callback function:
JavaScript
function greet(name, callback) {
console.log(‘Hello, ‘ + name);
callback();
}
function sayGoodbye() {
console.log(‘Goodbye!’);
}
greet(‘John’, sayGoodbye);
In this example, the greet() function takes two arguments: a name and a callback function. The greet() function prints a greeting to the console and then calls the callback function. The sayGoodbye() function is the callback function in this example.
When the greet() function is called, it prints a greeting to the console and then calls the sayGoodbye() function. The sayGoodbye() function prints a goodbye message to the console.
**
**Callback functions are a powerful tool for developing asynchronous JavaScript code. They allow you to execute code after another function has finished executing. This can be useful for a variety of tasks, such as fetching data from a server or updating the UI after a user interaction.