Função de retorno de chamada JS
function greeting(name) {
alert('Hello ' + name);
}
function processUserInput(callback) {
var name = prompt('Please enter your name.');
callback(name);
}
processUserInput(greeting);
function greeting(name) {
alert('Hello ' + name);
}
function processUserInput(callback) {
var name = prompt('Please enter your name.');
callback(name);
}
processUserInput(greeting);function sum(num1,num2,callback){
let total = num1 + num2
callback(total)
}
sum(10,20,function(total){
// received total here
console.log(total);
})
sum(5,16,(total)=>{
console.log(total);
})function startWith(message, callback){
console.log("Clearly written messages is: " + message);
//check if the callback variable is a function..
if(typeof callback == "function"){
callback(); //execute function if function is truly a function.
}
}
//finally execute function at the end
startWith("This Messsage", function mySpecialCallback(){
console.log("Message from callback function");
})const add = (num1, num2) => num1 + num2;
const result = (num1, num2, cb) => {
return "result is:" + cb(num1, num2);
}
const res = result(12, 13, add);function myFirst() {
myDisplayer("Hello");
}
function mySecond() {
myDisplayer("Goodbye");
}
myFirst();
mySecond();/*
A callback function is a function passed into another function
as an argument, which is then invoked inside the outer function
to complete some kind of routine or action.
*/
function greeting(name) {
alert('Hello ' + name);
}
function processUserInput(callback) {
var name = prompt('Please enter your name.');
callback(name);
}
processUserInput(greeting);
// The above example is a synchronous callback, as it is executed immediately.