Promise
- 자바스크립트 비동기 처리에 사용되는 객체.
let promise = new Promise(function(resolve, reject) {
resolve("done");
reject(new Error("…")); // 무시됨
});
ex>
let promise = Promise.all([...promises...]);
> 코드
function run(ms){
return new Promise(resolve =>setTimeout(resolve, ms));
}
const add =async ()=>{
await run(1000);
return 'add success!';
}
const update =async ()=>{
await run(2000);
return 'updated!';
}
const delete =async ()=>{
await run(3000);
return 'del!';
}
async function process(){
const results = await Promise.all([add(),update(),delete()]);
console.log(results);
}
process()
> 결과
["add success!", "update!", "del!"]