Remove objects from an Array based on values in another array

Question

I am trying to create an array with 7 objects (each per day). Idea is to create store hours for 7 days.

Final Dictionary will be like this:

    const storeHours = {
      monday: { startTime: mondayTime1, endTime: mondayTime1 },
      tuesday: { startTime: new Date(), endTime: new Date() },
      wednesday: { startTime: new Date(), endTime: new Date() },
//  other days ...
    };

I have 7 checkboxes, one for each day.

When I click checkbox, it stores checked item in an array.

checkedValues = ["Friday", "Saturday"]

I can use this checkedValues items to know which entry to make in newDict.

like this:

newDict = {
monday: { startTime: mondayTime1, endTime: mondayTime1 },
}

When I click second checkbox, newDict should have new entry for that day and so on.

When I un-check the checkbox I have to also remove the entry from this dictionary, so both, checkbox and dictionary, remain in sync.

how do I remove an entry from dictionary when an item is un-checked?

Whole idea is to basically store store hours in database with dictionary with 7 objects..

`finalArray ` is not an _array_: you have created an array containing a single dictionary and you have saved entries in the dictionary. This seems inefficient. Just create a dictionary, remove square brackets: `finalArray = {...}` — Andry, Jul 27 '20 at 06:31
yes I still have checkedValues array that holds checked items. — newdeveloper, Jul 27 '20 at 06:51

score 1 · Answer 1 · answered Jul 27 '20 at 06:37

I am not sure what you are trying to achieve here, please edit your question to make it more clear. So, as far as I can understand, here is a possible solution.

1. Store your entries in a dictionary

As your code is right now, finalArray is an array containing a single dictionary that you use to store entries. That is inefficient, just use the dictionary:

finalDict = {
  Friday: {startTime: startTime}, 
  Saturday: {endTime: endTime}
}

And since it is not an array, but a dictionary, I have renamed it accordingly to avoid confusion.

2. Set the entry to `null`

The cool thing of using dictionaries, is that you can reference an entry by its name. So, if Saturday is marked, then you need to simple:

finalDict.Saturday = null;

Or:

finalDict["Saturday"] = null;

After you do that, your dictionary will have the following value:

{
  Friday: {startTime: startTime}, 
  Saturday: null
}

tdranv · Accepted Answer · 2020-07-27T06:59:03.433

Assuming you still have the array with checkedValues you can use .filter() and then .reduce() to leave only the days from checkedValues. Also, you can use Object.keys() which will return the names of storeHours's keys.

const checkedValues = ["monday", "tuesday"];

const storeHours = {
  monday: { startTime: 1, endTime: 3 },
  tuesday: { startTime: new Date(), endTime: new Date() },
  wednesday: { startTime: new Date(), endTime: new Date() },
  //  other days ...
};

const newDict = Object.keys(storeHours)
  .filter(day => checkedValues.includes(day))
  .reduce((obj, key) => {
    obj[key] = storeHours[key];
    return obj;
  }, {});;

console.log(newDict);

This returns:

{
  "monday": {
    "startTime": 1,
    "endTime": 3
  },
  "tuesday": {
    "startTime": "2020-07-27T06:50:27.858Z",
    "endTime": "2020-07-27T06:50:27.858Z"
  }
}

Remove objects from an Array based on values in another array

2 Answers2

1. Store your entries in a dictionary

2. Set the entry to null

2. Set the entry to `null`