Page 64 - Nodejs 교과서 개정2판

resolve('성공');
} else {
reject('실패');
}
});
// 다른 코드가 들어갈 수 있음
promise
.then((message) => {
console.log(message); // 성공(resolve)한 경우 실행
})
.catch((error) => {
console.error(error); // 실패(reject)한 경우 실행
})
.finally(() => { // 끝나고 무조건 실행
console.log('무조건');
});

new Promise۽ ೐۽޷झܳ ࢤࢿೡ ࣻ ੓ਵݴ Ӓ ղࠗী resolve৬ rejectܳ ݒѐ߸ࣻ۽ ыח ௒ߔ ೣࣻܳ ֍
णפ׮ ੉ۧѱ ݅ٚ promise ߸ࣻী thenҗ catch ݫࢲ٘ܳ ࠢੌ ࣻ ੓णפ׮ ೐۽޷झ ղࠗীࢲ resolveо

ഐ୹غݶ then੉ प೯غҊ rejectо ഐ୹غݶ catchо प೯ؾפ׮ finally ࠗ࠙਷ ࢿҕ पಁ ৈࠗ৬ ࢚ҙহ
੉ प೯ؾפ׮

resolve৬ rejectী ֍যળ ੋࣻח пп thenҗ catch੄ ݒѐ߸ࣻীࢲ ߉ਸ ࣻ ੓णפ׮ ૊ resolve('성공'
)੉ ഐ୹غݶ then੄ messageо '성공'੉ ؾפ׮ ݅ড reject('실패')о ഐ୹غݶ DBUDI੄ errorо '실패'

о غח Ѫੑפ׮ condition ߸ࣻܳ false۽ ߄Լࠁݶ catchীࢲ ী۞о ۽Ӧؾפ׮

೐۽޷झܳ औѱ ࢸݺೞ੗ݶ प೯਷ ߄۽ ೞغ ѾҞч਷ ա઺ী ߉ח ё୓ੑפ׮ ѾҞч਷ प೯੉ ৮ܐػ റ t

hen੉ա catch ݫࢲ٘ܳ ా೧ ߉णפ׮ ਤ ৘ઁীࢲח new Promise৬ promise.then ࢎ੉ী ׮ܲ ௏٘о ٜয

т ࣻب ੓णפ׮ new Promiseח ߄۽ प೯غ૑݅ ѾҞч਷ thenਸ ࠢ৓ਸ ٸ ߉ѱ ؾפ׮

then੉ա catchীࢲ ׮द ׮ܲ UIFO੉ա catchܳ ࠢੌ ࣻ ੓णפ׮ ੉੹ then੄ return чਸ ׮਺ then੄ ݒ

ѐ߸ࣻ۽ ֈӤפ׮ ೐۽޷झܳ returnೠ ҃਋ীח ೐۽޷झо ࣻ೯ػ റ ׮਺ UIFO੉ա catchо ഐ୹ؾפ׮

promise
.then((message) => {
return new Promise((resolve, reject) => {
resolve(message);
});
})
.then((message2) => {
console.log(message2);