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JavaScript

Posted by Abe Layee
Abe Layee
8,378 Points

Js call back function

I understand that that call back functions are functions that call another function. My question is can anyone please explain this line below to me? I am lost where we passed callback as an argument and then we invoke the callback(). That part got me lost.

function sayHello() {
  console.log("This is an example of callback function in javaScript");

}

  function executeFunction(callback) {
     callback(); // please explain this part to me. Is this a way of calling sayHello() function?
  }

executeFunction(sayHello);

2 Answers

Andy Watts
Andy Watts
20,836 Points
Andy Watts
Andy Watts
20,836 Points

Yes, you are correct, calling callback() runs the function that was passed in to the function as a parameter, so it will run the sayHello function.

Abe Layee
Abe Layee
8,378 Points
Abe Layee
Abe Layee
8,378 Points

thank you