filter对数组和对象的过滤

1，对数组的过滤

      let arr = ['1', '2', '3']
      let b = arr.filter(val => val === '2')
      console.log(b) // ['2]

2，对象的过滤

      let objArr = [
        {id: 1, label: '影视'},
        {id: 2, label: '动漫'},
        {id: 3, label: '音乐'}
      ]
      let c = objArr.filter(val => {
        return val.label === '音乐'
      })
      console.log(c) // {id: 3, label: "音乐"}