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JavaScript

Posted by Edwin Carbajal
Edwin Carbajal
4,133 Points

Function Callbacks

Can someone please explain how function callbacks work? I am a little confused. I would like to know how they work and also why we pass in a function as a callback. And what is the definition of 'callback'?

const example = function('something', () => {
 // Do something here..
});

1 Answer

Joseph Frazer
Joseph Frazer
5,404 Points
Joseph Frazer
Joseph Frazer
5,404 Points

I will show you and explain how to make a callback function. First create your function with any parameter name:

function myFunction(callbackName) {
// Leave empty for now
}

Next we call the function in the function:

function myFunction(callbackName) {
callbackName();
}

Next lets call our magnificent function, but lets do something tricky:

function myFunctionTwo() {
console.log('Hello');

myFunction(myFunctionTwo);
}

Here we call our function in a function. It's an ordinary parameter, but in the function code, we call that parameter as a function. If you need me to explain it more in depth please ask me.