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 add(a, b, callback) {
if (callback && typeof(callback) === "function") {
callback(a + b);
}
}
add(5, 3, function(answer) {
console.log(answer);
});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);// Callback Function Example
function greet(name, myFunction) {
console.log('Hello world');
// callback function
// executed only after the greet() is executed
myFunction(name);
}
// callback function
function sayName(name) {
console.log('Hello' + ' ' + name);
}
// calling the function after 2 seconds
setTimeout(greet, 2000, 'John', sayName);