js处理数组数据常用方法

1、对象数组中取键值，返回键值数组

let arr = [{
      id: '1',
      name: 'one'
    },
    {
      id: '2',
      name: 'two'
    },
    {
      id: '3',
      name: 'three'
    }
  ]
  let newArr=arr.map(item=>item.id)
  console.log(newArr)

2、对象数组中取满足条件的键值（返回数组）

let arr = [{
     id: '1',
      name: 'one'
    },
    {
      id: '2',
      name: 'two'
    },
    {
      id: '3',
      name: 'three'
    }
  ]
  let newArr=arr.filter(item=>item.id==='2')
  console.log(newArr)

3、对象数组中取满足条件的键值（返回对象）

let arr = [{
     id: '1',
      name: 'one'
    },
    {
      id: '2',
      name: 'two'
    },
    {
      id: '3',
      name: 'three'
    }
  ]
  let newArr = arr.find(item => item.id === '2')
  console.log(newArr)