迅速了解一下ES10中Object.fromEntries的用法使用

const obj = { a: '1', b: 2 }
Object.entries(obj)

new Map(Object.entries(obj))
// Map(2) {"a" => "1", "b" => 2}

Object.fromEntries([['a', '1'], ['b', 2]])

const map = new Map().set('a', 1).set('b', 2)

Object.fromEntries(map)

Object.fromEntries([['a', '1'], ['a', '2']])

Object.fromEntries([[s, 1]])
Object.entries({ s: 1 })

obj = {}
obj[Symbol.iterator] = function* () {
  yield [1, 11]
  yield [2, 22]
  yield [3, 33]
}

console.dir(Object.fromEntries(obj))

function foo(obj, ...keys) {
  return Object.fromEntries(Object.entries(obj)
    .filter(([key]) => keys.includes(key))
  )
}

console.table(foo({ name: 'oli', age: '12' }, 'name'))

[{
  name: 'oli',
  age: 12
}, {
  name: 'troy',
  age: 14
}]

arr = [{
  name: 'oli',
  age: 12
}, {
  name: 'troy',
  age: 14
}]

obj = Object.fromEntries(
  arr.map(({name, age}) => [name, age])
)

console.table(obj)

function foo(obj) {
  return Object.fromEntries(Object.entries(obj)
    .map(([key, value]) => [value, key])
  )
}

console.table({ name: 'oli', age: '12' })
console.table(foo({ name: 'oli', age: '12' }))

query = Object.fromEntries(new URLSearchParams('foo=bar&baz=qux'))
// {foo: "bar", baz: "qux"}