javascript - 从 (JSON) 对象获取具有最高值的特定键

Question

我正在从 API 响应中获取数据，并尝试以最快的速度获取球场的名称。以下是 API 响应的示例。

{
page: 1,
total_pages: 4,
listings: [
    {
        name: "A.J. Burnett",
        pitches: [
            {
                name: "4 Seam FB",
                speed: 96,
                control: 84,
            },
            {
                name: "Knuckle Curve",
                speed: 79,
                control: 74,
            },
            {
                name: "Sinker",
                speed: 95,
                control: 64,
            },
            {
                name: "Changeup",
                speed: 81,
                control: 44,
            }
        ]
    },
    {
        name: "Joe Smitch",
        pitches: [
            {
                name: "4 Seam FB",
                speed: 91,
                control: 82,
            },
            {
                name: "Changeup",
                speed: 69,
                control: 44,
            }
        ]
    },
]
}

这是我尝试过的:

itemSet.forEach( (item) => {
    let fastestPitch = Object.keys(item.pitches).reduce((a, b) => {
        item.pitches[a] > item.pitches[b] ? item.pitches[a].name : item.pitches[b].name
     });
});

但是，这始终返回数组中最后一个音高的名称。我正在尝试以最快的速度返回球场。

编辑:我也尝试了以下操作，但它返回错误。

itemSet.forEach( (item) => {
    let fastestPitch = Object.keys(item.pitches).reduce((a, b) => {
        item.pitches[a].speed > item.pitches[b].speed ? item.pitches[a].name : item.pitches[b].name
     });
});

错误:

(node:80698) UnhandledPromiseRejectionWarning: TypeError: Cannot read property 'speed' of undefined

Answer 1

你可以这样做:

const data = {
  page: 1,
  total_pages: 4,
  listings: [{
      name: "A.J. Burnett",
      pitches: [{
          name: "4 Seam FB",
          speed: 96,
          control: 84,
        },
        {
          name: "Knuckle Curve",
          speed: 79,
          control: 74,
        },
        {
          name: "Sinker",
          speed: 95,
          control: 64,
        },
        {
          name: "Changeup",
          speed: 81,
          control: 44,
        }
      ]
    },
    {
      name: "Joe Smitch",
      pitches: [{
          name: "4 Seam FB",
          speed: 91,
          control: 82,
        },
        {
          name: "Changeup",
          speed: 69,
          control: 44,
        }
      ]
    },
  ]
}

const fastesPitches = data.listings.map(({ pitches }) => {
  return pitches.reduce((a, c) => c.speed > a.speed ? c : a).name;
});

console.log(fastesPitches);