JavaScript-da Promise-larda istisnolarni alohida tutish
then-da faqat istisno holatini qayta ishlovchi funktsiyani
ko'rsatish mumkin, birinchi
parametr o'rniga null berish orqali:
promise.then(
null,
function(error) {
console.log(error);
}
);
Bunday holatda catch metodi orqali qisqartirilgan
sintaksisdan foydalanish qulay:
promise.catch(
function(error) {
console.log(error);
}
);
Quyidagi kodni catch metodi orqali qayta yozing:
let promise = new Promise(function(resolve, reject) {
setTimeout(function() {
let isError = false;
if (!isError) {
resolve('success');
} else {
reject(new Error('error'));
}
}, 3000);
});
promise.then(
res => console.log(res),
err => console.log(err.message),
);
