How do I store data in an array if the data is more than 1?

Question

I have this script:

    let data = [
        {day: 1, time: '08:00', note: 'madrid'},
        {day: 2, time: '08:00', note: 'barcelona'},
        {day: 3, time: '10:00', note: 'juventus'},
    ]
    let days = [7, 1, 2, 3, 4, 5, 6]
    let list = []

    days.forEach(element => {
        let item = data.find(x => x.day === element)

        if (item) {
            list.push(item)
        } else {
            list.push({ day: element, time: undefined })
        }
    });

If the script is executed, it works. It will show schedule from day 1 to day 7. However, my problem is that the data variable is dynamic. So one day may have more than one schedule, like here:

    let data = [
      {day: 1, time: '08:00', note: 'madrid'}, {day: 1, time: '09:00', note: 'chelsea'},
      {day: 2, time: '08:00', note: 'barcelona'}, {day: 2, time: '09:00', note: 'mu'},
      {day: 3, time: '10:00', note: 'juventus'}
    ]

Maybe I should make an inner array per day (day as the key), so I can save data days that have more than one schedule.

How do I do that?

Answer 1

Would you be able to do something like this?

let data = [
    {day: 1, time: '08:00', note: 'madrid'}, {day: 1, time: '09:00', note: 'chelsea'},
    {day: 2, time: '08:00', note: 'barcelona'}, {day: 2, time: '09:00', note: 'mu'},
    {day: 3, time: '10:00', note: 'juventus'}
]
let days = [7, 1, 2, 3, 4, 5, 6];
let list = [];

days.forEach(day => {
    list.push({day, schedule: [...data.filter(d => d.day === day)]
        .map(d => ({time: d.time, note: d.note}))
    })
});

console.log(list);

Answer 2

Okay, let's say you have this:

let days = [7, 1, 2, 3, 4, 5, 6]

let data = [
    {day: 1, time: '08:00', note: 'madrid'},
    {day: 1, time: '09:00', note: 'chelsea'},
    {day: 2, time: '08:00', note: 'barcelona'},
    {day: 2, time: '09:00', note: 'mu'},
    {day: 3, time: '10:00', note: 'juventus'}
]

I first would filter the data array to obtain all objects with your key, and then I would push all those items to the list result variable. One approach for that could be:

days.forEach( d => {
    let daySchedule = data.filter(elem => {
        elem.day === d;
    });

    if (daySchedule.length > 0) {
        daySchedule.forEach( elem => list.push(elem) );
    }
    else {
        list.push({ day: d, time: undefined })
    }
});