无法在javascript中获取最后一个数组

Question

const search = await spot.search(request, {
  limit: 3,
  type: ['track']
});
search.tracks.items.forEach(song => {
  let tableArtists = []
  song.artists.forEach(artist => {
    if (song.artists[0].name == artist.name) return tableArtists.push(artist.name)
    if (song.artists[song.artists.length].name == artist.name) return tableArtists.push(" & " + artist.name)
    tableArtists.push(", " + artist.name)
  })
  console.log(song.name + " - " + tableArtists.join(" "))
})

这个代码应该得到一首歌曲中的所有艺术家，最后一个以&符号开头。目前，它不会得到最后一位艺术家的名字。为什么？仅供参考：song.artists.last() 也不起作用。

Answer 1

song.artists 数组的最后一个元素的索引不是song.artists.length 而是song.artists.length - 1

替换

if (song.artists[song.artists.length].name == artist.name) return tableArtists.push(" & " + artist.name)

与

if (song.artists[song.artists.length - 1].name == artist.name) return tableArtists.push(" & " + artist.name)

Answer 2

搜索响应：

Track {
  availableMarkets:
   [ 'AD',
     'AE',
     'AG',
     'AL',
     'AM',
     'AO',
     'AR',
     'AT',
     'AZ',
     'BA',
     'BB',
     'BD',
     'BF',
     'BG',
     'BH',
     'BI',
     'BJ',
     'BN',
     'BO',
     'BR',
     'BS',
     'BW',
     'BY',
     'BZ',
     'CA',
     'CH',
     'CI',
     'CL',
     'CM',
     'CO',
     'CR',
     'CV',
     'CW',
     'CY',
     'CZ',
     'DE',
     'DJ',
     'DK',
     'DM',
     'DO',
     'DZ',
     'EC',
     'EE',
     'EG',
     'FI',
     'FJ',
     'FM',
     'FR',
     'GA',
     'GB',
     'GD',
     'GH',
     'GM',
     'GN',
     'GQ',
     'GR',
     'GT',
     'GW',
     'HK',
     'HN',
     'HR',
     'HT',
     'HU',
     'ID',
     'IE',
     'IL',
     'IN',
     'IS',
     'IT',
     'JM',
     'JO',
     'JP',
     'KE',
     'KG',
     'KH',
     'KM',
     'KN',
     'KR',
     'KW',
     'KZ',
     'LA',
     'LB',
     'LC',
     'LK',
     'LR',
     'LS',
     'LT',
     'LV',
     'MA',
     'MC',
     'MD',
     'ME',
     'MG',
     'MK',
     'ML',
     'MN',
     'MO',
     'MR',
     'MT',
     'MU',
     ... 55 more items ],
  discNumber: 1,
  duration: 165440,
  explicit: false,
  externalUrls:
   { spotify: 'https://open.spotify.com/track/483XiZ5o13Cc1zoWV7jGml' },
  href: 'https://api.spotify.com/v1/tracks/483XiZ5o13Cc1zoWV7jGml',
  id: '483XiZ5o13Cc1zoWV7jGml',
  name: 'Gecko (Overdrive) - Radio Edit',
  previewUrl:
   'https://p.scdn.co/mp3-preview/9ed94074e04a78652aecf9f4c58ebffe9cd16fbd?cid=ac37a89f1e77422e955b85f07d8a6cdb',
  trackNumber: 1,
  type: 'track',
  uri: 'spotify:track:483XiZ5o13Cc1zoWV7jGml',
  playable: undefined,
  local: false,
  externalIds: { isrc: 'CYA111400063' },
  popularity: 70,
  restrictions: null }