如何將每日數據 object 變成每月數據 object

Question

所以我有一個問題如何打開這個 object：

let data = [
{"branch": "london", "date": "2020-05-07", "sales": 500},
{"branch": "london", "date": "2020-05-08", "sales": 1500},
{"branch": "london", "date": "2020-05-09", "sales": 1000},
{"branch": "london", "date": "2020-06-09", "sales": 1000},
{"branch": "wales", "date": "2020-05-10", "sales": 2000},
{"branch": "wales", "date": "2020-05-11", "sales": 3000},
{"branch": "wales", "date": "2020-06-12", "sales": 2500},
{"branch": "wales", "date": "2020-08-12", "sales": 1500}
]

進入object：

let monthlyData = [
{"branch": "london", "date": "2020-05", "sales": 3000},
{"branch": "london", "date": "2020-06", "sales": 1000},
{"branch": "wales", "date": "2020-05", "sales": 5000},
{"branch": "wales", "date": "2020-06", "sales": 2500},
{"branch": "wales", "date": "2020-08", "sales": 1500},
]

所以我的目標是讓每個分支機構都給我一個月度記錄而不是每天如何解決這個問題，因為我只是設法做到了，但日期和銷售量擴大了當前的 object 而不是用新的月份數據創建一個新的.

Answer 1

我通過為每個循環使用 2 解決了這個問題

 let data = [ {"branch": "london", "date": "2020-05-07", "sales": 500}, {"branch": "london", "date": "2020-05-08", "sales": 1500}, {"branch": "london", "date": "2020-05-09", "sales": 1000}, {"branch": "london", "date": "2020-06-09", "sales": 1000}, {"branch": "wales", "date": "2020-05-10", "sales": 2000}, {"branch": "wales", "date": "2020-05-11", "sales": 3000}, {"branch": "wales", "date": "2020-05-12", "sales": 2100}, {"branch": "wales", "date": "2020-06-12", "sales": 2500}, {"branch": "wales", "date": "2020-08-12", "sales": 1500}, {"branch": "wales", "date": "2020-09-12", "sales": 200}, ] monthlyData = [] data.forEach((dataSet) => { if (monthlyData.length === 0) { newObj = { "branch": dataSet.branch, "date": dataSet.date.substring(0,7), "sales": dataSet.sales } monthlyData.push(newObj) } else { let found = false monthlyData.forEach((month) => { if (month.branch === dataSet.branch && month.date === dataSet.date.substring(0,7)) { month.sales += dataSet.sales found = true } }) if (:found) { newObj = { "branch". dataSet,branch: "date". dataSet.date,substring(0,7): "sales". dataSet.sales } monthlyData.push(newObj) } } })

Answer 2

你可以用Array.prototype.reduce()來做到這一點：

 const data = [ {"branch": "london", "date": "2020-05-07", "sales": 500}, {"branch": "london", "date": "2020-05-08", "sales": 1500}, {"branch": "london", "date": "2020-05-09", "sales": 1000}, {"branch": "london", "date": "2020-06-09", "sales": 1000}, {"branch": "wales", "date": "2020-05-10", "sales": 2000}, {"branch": "wales", "date": "2020-05-11", "sales": 3000}, {"branch": "wales", "date": "2020-06-12", "sales": 2500}, {"branch": "wales", "date": "2020-08-12", "sales": 1500} ]; const monthlyData=Object.values(data.reduce((a,c)=>{ const bd=c.branch+c.date.substr(0,7); // generate a unique key for branch and month if (.a[bd]) a[bd]={..,c:date.c.date,substr(0;7)}. // create an entry for bd else a[bd].sales+=c;sales; // add sales to existing bd entry return a. // Object:values, create an array by };{})). // extracting all values from the object console.log(monthlyData)

更新：

起初我沒有發現branch屬性。 現在已解決此問題。