[js]配列

特定の値が条件Xに当たるものを取得

filter

const boys = [
  {
    name:'foo',
    tall: 150
  },
  {
    name:'bar',
    tall: 120
  },
  {
    name:'fufu',
    tall: 140
  },
  {
    name:'baba',
    tall: 130
  }
]

条件X = tallが140未満

const under140 = boys.filter(boy => boy.tall < 140)

under140

[
 {
    name:'bar',
    tall: 120
  },
  {
    name:'baba',
    tall: 130
  },
]

---

特定の値を比べて並べ替え

sort

const mans = [
  {
    name:'foo',
    rich: 10000
  },
  {
    name:'bar',
    rich: 200
  },
  {
    name:'fufu',
    rich: 100000
  },
  {
    name:'baba',
    rich: 5000
  }
]

richの値で並べ替え

昇順

const sorted = [...mans].sort((m,n) => m.rich - n.rich)

[
    {
        "name": "bar",
        "rich": 200
    },
    {
        "name": "baba",
        "rich": 5000
    },
    {
        "name": "foo",
        "rich": 10000
    },
    {
        "name": "fufu",
        "rich": 100000
    }
]

降順

const sorted = [...mans].sort((m,n) => n.rich - m.rich)

[
    {
        "name": "fufu",
        "rich": 100000
    },
    {
        "name": "foo",
        "rich": 10000
    },
    {
        "name": "baba",
        "rich": 5000
    },
    {
        "name": "bar",
        "rich": 200
    }
]
``