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!
seat.Booked(true);
}
viewModel.seats()[self.No()].Booked(true);
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