여러 음악이 있다고 해
아래 코드는 모든 장르의 모든 제목을 반환합니다. 하지만 컨트리 장르의 노래 제목 만 원합니다.
const music= [{
"title": "Cheats",
"year": 2018,
"cast": ["Jane Rhee", "Kacey Brown"],
"genres": ["Country"]
}, {
"title": "Road",
"year": 2018,
"cast": ["Jeff Bates", "Alan Walker", "Cindy Bates"],
"genres": ["Country"]
}, {
"title": "Trail Down",
"year": 2018,
"cast": ["Ken Clemont"],
"genres": ["Jazz"]
}, {
"title": "Way Down",
"year": 2018,
"cast": ["Denzel Harr", "Dan Smith", "Lee Kyle", "Nate Hill"],
"genres": ["Pop"]
}, {
"title": "Fountain",
"year": 2018,
"cast": ["Brad Smith", "Rosa King"],
"genres": ["Rock"]
}, {
"title": "Gold Bells",
"year": 2018,
"cast": ["Paisley John"],
"genres": ["Blues"]
}, {
"title": "Mountain Curve",
"year": 2018,
"cast": ["Michael Johnson"],
"genres": ["Country"]
}, {
"title": "Arabella",
"year": 2018,
"cast": [],
"genres": ["Jazz"]
}, {
"title": "Curved",
"year": 2018,
"cast": ["Brett Shay"],
"genres": ["Country"]
}];
let songs = [];
for (var i = 0; i < music.length; i++) {
songs.push(music[i].title);
}
console.log(songs);.filterCountry장르에 포함 되는지 여부에 따른 배열 , 다음 .map제목 :
const music=[{title:"Cheats",year:2018,cast:["Jane Rhee","Kacey Brown"],genres:["Country"]},{title:"Road",year:2018,cast:["Jeff Bates","Alan Walker","Cindy Bates"],genres:["Country"]},{title:"Trail Down",year:2018,cast:["Ken Clemont"],genres:["Jazz"]},{title:"Way Down",year:2018,cast:["Denzel Harr","Dan Smith","Lee Kyle","Nate Hill"],genres:["Pop"]},{title:"Fountain",year:2018,cast:["Brad Smith","Rosa King"],genres:["Rock"]},{title:"Gold Bells",year:2018,cast:["Paisley John"],genres:["Blues"]},{title:"Mountain Curve",year:2018,cast:["Michael Johnson"],genres:["Country"]},{title:"Arabella",year:2018,cast:[],genres:["Jazz"]},{title:"Curved",year:2018,cast:["Brett Shay"],genres:["Country"]}];
const countryTitles = music
.filter(({ genres }) => genres.includes('Country'))
.map(({ title }) => title);
console.log(countryTitles)데이터 세트를 한 번만 반복하면서 수행하려면 reduce대신 사용하십시오.
const music=[{title:"Cheats",year:2018,cast:["Jane Rhee","Kacey Brown"],genres:["Country"]},{title:"Road",year:2018,cast:["Jeff Bates","Alan Walker","Cindy Bates"],genres:["Country"]},{title:"Trail Down",year:2018,cast:["Ken Clemont"],genres:["Jazz"]},{title:"Way Down",year:2018,cast:["Denzel Harr","Dan Smith","Lee Kyle","Nate Hill"],genres:["Pop"]},{title:"Fountain",year:2018,cast:["Brad Smith","Rosa King"],genres:["Rock"]},{title:"Gold Bells",year:2018,cast:["Paisley John"],genres:["Blues"]},{title:"Mountain Curve",year:2018,cast:["Michael Johnson"],genres:["Country"]},{title:"Arabella",year:2018,cast:[],genres:["Jazz"]},{title:"Curved",year:2018,cast:["Brett Shay"],genres:["Country"]}];
const countryTitles = music
.reduce((a, { genres, title }) => {
if (genres.includes('Country')) {
a.push(title)
}
return a;
}, []);
console.log(countryTitles)이 기사는 인터넷에서 수집됩니다. 재 인쇄 할 때 출처를 알려주십시오.
침해가 발생한 경우 연락 주시기 바랍니다[email protected] 삭제
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