can anyone give me an example in which we are creating a particular function, which is also having a callback function ?
function login(username, password, function(err,result){
});
where should I put the code of the login function and callback function?
p.s.: I am new to nodejs
Here's an example of the login function:
function login(username, password, callback) {
var info = {user: username, pwd: password};
request.post({url: "https://www.adomain.com/login", formData: info}, function(err, response) {
callback(err, response);
});
}
And calling the login function
login("bob", "wonderland", function(err, result) {
if (err) {
// login did not succeed
} else {
// login successful
}
});
bad question but w/e
you have mixed up invoking and defining an asynchronous function:
// define async function:
function login(username, password, callback){
console.log('I will be logged second');
// Another async call nested inside. A common pattern:
setTimeout(function(){
console.log('I will be logged third');
callback(null, {});
}, 1000);
};
// invoke async function:
console.log('I will be logged first');
login(username, password, function(err,result){
console.log('I will be logged fourth');
console.log('The user is', result)
});
