Removing an item from an array containing several objects

I have an array that looks like this:

var participants = [
  {username: "john", time: null}, 
  {username: "samira", time: null}, 
  {username: "mike", time: null}, 
  {username: "son", time:null}
]

To remove an item based on the username, I can do the following:

const index = participants.map(x => {

  x.map(y => {
      return y.username;
    })
  }).indexOf(username); //get index of username

participants.splice(index, 1);

After removing the item, if the index of the username returns "-1", does that mean the participants array becomes empty?

The expected output after removing the item with username 'son' would be:

[
  {username: "john", time: null}, 
  {username: "samira", time: null}, 
  {username: "mike", time: null}
]

UPDATE:

It turns out that my array is nested within another array, as shown in the image below:

https://i.sstatic.net/jVhZG.png

Answer №1

To filter out specific items from an array, one can utilize the Array.filter() method.

participants.filter((participant) => participant.name !== userName)

Answer №2

If you want to remove an element from an array in JavaScript, there are a few ways to do it. One option is to use the filter method, or you can also achieve this by using splice and map like so:

participants.splice(participants.map(x => x.username).indexOf(username),1);

Answer №3

One way to manipulate arrays is by using the filter function. However, it's important to note that filter does not modify the original array. Therefore, you will need to assign the filtered results back to the original variable like so: participants = participants.filter((item) => item.username !== username))

Answer №4

give this a shot

let user = 'son';

for(let j= 0; j < userList.length; j++) {
    if(userList[j].user == user) {
        userList.splice(j, 1);
        j--;
    }
}

NOTE: filter, map and other alternatives enhance code readability compared to for loops, but the latter are more efficient for performance optimization. Choose based on your specific requirements.

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