Updating Knockout.js Observable array element value

I need to update an observable array element value.
The observable array is a collection of class objects.
First I need to find out matching object by id and update some other property values of the object.

var Seat = function(no, booked) {
    var self = this;
    self.No = ko.observable(no);
    self.Booked = ko.observable(!!booked);

    // Subscribe to the "Booked" property
    self.Booked.subscribe(function() {
        alert( self.No() );

var viewModel = {
    seats: ko.observableArray( [
        new Seat(1, false), new Seat(2, true), new Seat(3, true),
        new Seat(4, false), new Seat(5, true), new Seat(6, true),
        new Seat(7, false), new Seat(8, true), new Seat(9, true)
    ] )

Can anyone suggest the approach of updating the view model?
Let’s say I want to update booked value to “false” for the seat no 2.


That’s pretty simple with knockout:

// We're looking for the Seat with this No 
var targetNo = 2;

// Search for the seat -> arrayFirst iterates over the array and returns the
// first item that is a match (= callback returns "true")!
var seat = ko.utils.arrayFirst(this.seats(), function(currentSeat) {
    return currentSeat.No() == targetNo; // <-- is this the desired seat?

// Seat found?
if (seat) {
    // Update the "Booked" property of this seat!



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