Fast classification of array.group() in ES6

ES6 Medium Array.group() Quickly sort and combine arrays

1. Need to rely on babel, Install... In the project first

npm i core-js

2. introduce

import 'core-js/actual/array/group

3. Application scenarios

I have an array , According to some information in the array , Grouping .
example ：
There is a set of customer information , Now it will be grouped according to provinces .

4. application

One line of code to solve

const orderList = [{
    
  nickName: 'steven',
  productName: ' watermelon ',
  price: 29,
  province: 'henan',
},{
    
  nickName: ' The other person's ',
  productName: ' Arbutus ',
  price: 22,
  province: 'shanxi',
},{
    
  nickName: ' Fan battery ',
  productName: ' Apple ',
  price: 19,
  province: 'dongbei',
},{
    
  nickName: ' survey v',
  productName: ' Peach ',
  price: 88,
  province: 'shanxi',
},{
    
  nickName: '2 Number ',
  productName: ' Peach ',
  price: 88,
  province: 'shanxi',
}]

const group=orderList.group(({
     province})=>province)
console.log(group)

5. Implementation when not in use

const provinceObj = {
    }
for (let index = 0; index < orderList.length; index++) {
    
  const element = orderList[index];  // This data of the cycle   object 
  const provinceKey = element.province // The province field in this data 
  //  Determine whether the attribute exists in the empty object , Yes key Values exist push
  if (provinceObj[provinceKey]) {
    
    provinceObj[provinceKey].push(element)
  } else {
    
    // key Create a new one if the value does not exist key and value
    provinceObj[provinceKey] = [element]  //[element]  Put this data into the array 
  }
}
console.log(provinceObj)

The results are the same