lodash分配键值对

Question

How do transform this

[ { '1491926400000': 222 }, { '1491926400000': 489 } ]

to this:

[ { date: '1491926400000', count: 222 }, { date: '1491926400000', count: 489 } ]

I have tried with 'reduce' and 'transform' using lodash but not going anywhere with it.

Answer 1

var oldArray = [ { '1491926400000': 222 }, { '1491926400000': 489 } ];
var newArray = [];
for(var i = 0; i < oldArray.length; i++){
  var originObject = oldArray[i];
  for(var key in originObject) {
    var value = originObject[key];
    var obj = {date: key, count: value};
    newArray.push(obj);
  }
}

does the transform

Answer 2

Possible solution using Array#map .

 var arr = [{ '1491926400000': 222 }, { '1491926400000': 489 }], res = arr.map(v => Object.assign({}, ...Object.keys(v).map(c => ({ date: c, count: v[c]})))); console.log(res); 

Answer 3

Here's a neat solution using lodash/fp (curried functions / data last):

const mapData = map(
  flowRight(
    zipObject(['date', 'count']),   // { date: '1491926400000', count: 222 }
    flatten,                        // ['1491926400000', 222]
    toPairs                         // [ ['1491926400000', 222] ]
  )
)

Same thing in regular lodash :

const mapData = (data) => map(data, (o) =>
  zipObject(['date', 'count'], flatten(toPairs(o)))
)

Usage for either:

mapData([ { '1491926400000': 222 }, { '1491926400000': 489 } ])

// [ { date: '1491926400000', count: 222 }, { date: '1491926400000', count: 489 } ]