JSON 对象数组。 按名称对对象值进行分组

Question

I'm trying to get with Javascript JSON object values to be grouped based on the name key word in the array that contains the objects this is a dynamic array so this cannot be hard coded.

the objects have time values in it

the time_entries array length changes.

the time_entries array can have 1 or more objects in it.

I want to group the objects by the time: Hour minutes seconds

{
    "activities": [
        {
            "name": "player one",
            "time_entries": [
                {
                    "days": 0,
                    "end_time": "2019-09-30 15:19:43",
                    "hours": 01,
                    "minutes": 02,
                    "seconds": 11,
                    "start_time": "2019-09-30 14:17:58"
                },
                {
                    "days": 0,
                    "end_time": "2019-09-25 15:40:11",
                    "hours": 0,
                    "minutes": 20,
                    "seconds": 4,
                    "start_time": "2019-09-25 15:20:15"
                },
                {
                    "days": 0,
                    "end_time": "2019-09-25 16:10:15",
                    "hours": 0,
                    "minutes": 30,
                    "seconds": 4,
                    "start_time": "2019-09-25 15:40:11"
                },

#there can be more objects here

            ]
        },
        {
            "name": "player two",
            "time_entries": [
                {
                    "days": 0,
                    "end_time": "2019-09-30 19:18:51",
                    "hours": 0,
                    "minutes": 0,
                    "seconds": 52,
                    "start_time": "2019-09-30 19:17:58"
                },

#there can be more objects here

            ]
        },
        {
            "name": "player three",
            "time_entries": [
                {
                    "days": 0,
                    "end_time": "2019-09-30 19:19:09",
                    "hours": 0,
                    "minutes": 0,
                    "seconds": 58,
                    "start_time": "2019-09-30 19:18:51"
                },
                {
                    "days": 0,
                    "end_time": "2019-09-30 21:21:09",
                    "hours": 2,
                    "minutes": 1,
                    "seconds": 0,
                    "start_time": "2019-09-30 19:20:09"
                },

#there can be more objects here

            ]
        }
    ]
}

What I want to get is something like this

 [
        {
            "name": "player one",
            "time_entries": [
                {
                    "days": 0,
                    "end_time": "2019-09-25 16:10:15",
                    "hours": 01,
                    "minutes": 50,
                    "seconds": 19,
                    "start_time": "2019-09-30 14:17:58"
                }
            ]
        },
        {
            "name": "player two",
            "time_entries": [
                {
                    "days": 0,
                    "end_time": "2019-09-30 19:18:51",
                    "hours": 0,
                    "minutes": 0,
                    "seconds": 52,
                    "start_time": "2019-09-30 19:17:58"
                }
            ]
        },
        {
            "name": "player three",
            "time_entries": [
                {
                    "days": 0,
                    "end_time":"2019-09-30 21:21:09",
                    "hours": 2,
                    "minutes": 1,
                    "seconds": 58,
                    "start_time": "2019-09-30 19:18:51"
                }
            ]
        }
]

Answer 1

You can do it as follows:

• Use map() method to iterate on given activities and transform each activity's time_entries property.
• getTimeEntry() method takes array of time entries and returns earliest start time, latest end time, and total activity time converted to days, hours, minutes, seconds .

 let data = { "activities": [ { "name": "player one", "time_entries": [ { "days": 0, "end_time": "2019-09-30 15:19:43", "hours": 01, "minutes": 02, "seconds": 11, "start_time": "2019-09-30 14:17:58" }, { "days": 0, "end_time": "2019-09-25 15:40:11", "hours": 0, "minutes": 20, "seconds": 4, "start_time": "2019-09-25 15:20:15" }, { "days": 0, "end_time": "2019-09-25 16:10:15", "hours": 0, "minutes": 30, "seconds": 4, "start_time": "2019-09-25 15:40:11" } ] }, { "name": "player two", "time_entries": [ { "days": 0, "end_time": "2019-09-30 19:18:51", "hours": 0, "minutes": 0, "seconds": 52, "start_time": "2019-09-30 19:17:58" } ] }, { "name": "player three", "time_entries": [ { "days": 0, "end_time": "2019-09-30 19:19:09", "hours": 0, "minutes": 0, "seconds": 58, "start_time": "2019-09-30 19:18:51" }, { "days": 0, "end_time": "2019-09-30 21:21:09", "hours": 2, "minutes": 1, "seconds": 0, "start_time": "2019-09-30 19:20:09" } ] } ] }; let result = {}; result.activities = data.activities.map(item => { return { "name": item.name, "time_entries": [getTimeEntry(item.time_entries)] }; }); function getTimeEntry(timeEntries) { let earliestTime = timeEntries[0].start_time; let latestTime = timeEntries[0].end_time; // Find earliest start time and latest end time. timeEntries.forEach(entry => { if (new Date(entry.start_time) < new Date(earliestTime)) { earliestTime = entry.start_time; } if (new Date(entry.end_time) > new Date(latestTime)) { latestTime = entry.end_time; } }); // Calculate total seconds. let seconds = timeEntries.reduce((totalSeconds, currentEntry) => { let seconds = 0; seconds += currentEntry.seconds; seconds += currentEntry.minutes * 60; seconds += currentEntry.hours * 60 * 60; seconds += currentEntry.days * 24 * 60 * 60; return totalSeconds + seconds; }, 0); // Convert total seconds to days, hours, minutes, and seconds. let days = Math.floor(seconds / (24 * 60 * 60)); seconds = seconds % (24 * 60 * 60); let hours = Math.floor(seconds / (60 * 60)); seconds = seconds % (60 * 60); let minutes = Math.floor(seconds / 60); seconds = seconds % 60; return { "start_time": earliestTime, "end_time": latestTime, "days": days, "hours": hours, "minutes": minutes, "seconds": seconds }; } console.log(result);