Nov 2, 2014 · Try iterating through the elements of the persons object, update the element if a member with the same name exists, if it doesn't, push a new element to the array. Use a new variable exists to check if the member existed. Here is what you could do: var persons = { data: [] }; var bob = {name: 'Bob', age: 15}; var fill = {name: 'Fill', age: 20};

The splice() method lets you insert new elements into an array while simultaneously deleting existing elements. To do this, you pass at least three arguments: the second argument specifies the number of items to delete, and the third argument indicates the element to insert.

export function addOrRemove<T>(source: T[], candidate: T, comparator?: (a: T, b: T) => boolean): T[] { const c = comparator || ((a, b) => a == b) const e = source.find(i => c(i, candidate)) return e ? source.filter(i => !c(i, candidate)) : [...source, candidate] } It will immutably toggle an array element (remove if it's present, add if not).

Dose your newer object item contains a id key? or do you mind having the id as well as all the properties from item object in the array entry? You can use findIndex to find the index in the array of the object and replace it as required: var item = {...} This assumes unique IDs.

Discover how to use JavaScript's .splice () method for array manipulation, including adding, removing, and replacing elements in arrays

The ability to modify arrays after they are created makes JavaScript flexible and dynamic. You often need to add, remove or update data stored in arrays as your program runs.

Feb 13, 2020 · In this tutorial we will create a Create, Read, Update, Delete (CRUD) using JavaScript. This code will add, delete, update and read a data table when the user open the program.

Mar 22, 2023 · The splice () method allows you to add or remove elements from an array. You can use it to replace an element by specifying the index, the number of elements to remove (which is 1 in this case), and the new element to add.

Nov 7, 2019 · const arrayOfBooks = [ {book: 1}, {book: 2}, {book: 3}, {book: 4}, ] const addBook = (list, book) => { list.push(book) } addBook(arrayOfBooks, {book: 5, isTheNewOne: true}) const result = arrayOfBooks console.log(result) // Array with 5 elements now See in fiddle

To add or remove from the end of an array, we use push and pop. To add or remove from the front, we use shift and unshift. We can use splice to insert or delete elements from any part of …