js use callback function code example

Example 1: create callback function javascript

function add(a, b, callback) {
  if (callback && typeof(callback) === "function") {
    callback(a + b);
  }
}

add(5, 3, function(answer) {
  console.log(answer);
});

Example 2: callback function

//Callback functions - are functions that are called AFTER something happened

  const foo = (number, callbackFunction) => {
    //first 
    console.log(number)
    
    //second - runs AFTER console.log() happened
    callbackFunction()
  }