강의노트 - 16

Async / Await

예시1)

const a = () => {
  return new Promise(resolve => {
    setTimeout(() => {
      console.log(1)
      resolve()
    }, 1000)
  })
}

const b = () => console.log(2)

const wrap = async () => {
  await a()
  b()
}

wrap()

Resolve, Reject를 async/await에서

const delayAdd = index => {
  return new Promise((resolve, reject) => {
    setTimeout(() => {
      if(index > 10) {
        reject(`${index}는 10보다 클 수 없습니다.`)
        return
      }
      console.log(index)
      resolve(index + 1)
    }, 1000)
  })
}

const wrap = async () => {
  try {
    const res = await delayAdd(12)
    console.log(res)
  }
  catch (err){
    console.error(err)
  }
}

wrap()

에러 핸들링

const getMovies = movieName => {
  return new Promise((resolve, reject) => {
    fetch(`https://www.omdbapi.com/?apikey=7035c60c&s=${movieName}`)
      .then(res => res.json())
      .then(json => {
        if (json.Response === 'False') {
          reject(json.Error)
        }
        resolve(json)
      })
      .catch(error => {
        reject(error)
      })
  })
}

let loading = true
getMovies('avengers')
  .then(movies => console.log('영화 목록:', movies))
  .catch(errpr => console.log('에러 발생', error))
  .finally(() => loading = false)