Explain callback functions in JavaScript with the help of an example.

1.	Explain callback functions in JavaScript with the help of an example.
Answer» A callback function is a function that receives an input from another function and is then called from within the OUTER function to COMPLETE a routine or operation. Here's an illustration of a callback function in JavaScript: function cityCallout(city) { alert('WELCOME to' + city + '!');}function FOO(callback) { var cityName = prompt('Please input the name of the city here:'); callback(cityName);}foo(cityCallout); Therefore, if we pass "New York" in the prompt, the output of this piece of code snippet will be "Welcome to New York!".

Answer»

A callback function is a function that receives an input from another function and is then called from within the OUTER function to COMPLETE a routine or operation. Here's an illustration of a callback function in JavaScript:

function cityCallout(city) { alert('WELCOME to' + city + '!');}function FOO(callback) { var cityName = prompt('Please input the name of the city here:'); callback(cityName);}foo(cityCallout);

Therefore, if we pass "New York" in the prompt, the output of this piece of code snippet will be "Welcome to New York!".

Discussion

No Comment Found

Related InterviewSolutions

What are the benefits and drawbacks of using a star topology in a computer network?
Write down a C++ function to display all the nodes in a circular linked list.
Give a few features of Hadoop.
How can one differentiate between local variables and global variables?
Can you please briefly describe the singleton design pattern in brief?
What do you understand about namespaces in Python?
What do you understand about functional programming in JavaScript?
Explain callback functions in JavaScript with the help of an example.
What do you understand about system calls?
What is the definition of marshalling?