Binding a list of objects to a list of checkboxes

Question

I have a list of objects, each with a few fields, like this:

function Person(id,name,age) {
    this.id = id;
    this.name = name;
    this.age = age;
}

va         


        

Answer 1

You can do something like:

<ul data-bind="foreach: people">
    <li>
        <input type="checkbox" 
               data-bind="checkedValue: id, checked: $parent.selectedPeople">
    </li>
</ul>

With this kind of ViewModel:

var viewModel = {
    people: ko.observableArray(listOfPeople),
    selectedPeople: ko.observableArray()
};

The value attribute controls what the checked binding adds/removes from an array when it is bound against an array. You could also write a dependentObservable that populates the array with the actual objects, if necessary.

Live Example:

function Person(id,name,age) {
    this.id = id;
    this.name = name;
    this.age = age;
}

var listOfPeople = [
    new Person(1, 'Fred', 25),
    new Person(2, 'Joe', 60),
    new Person(3, 'Sally', 43)
];

var viewModel = {
    people: ko.observableArray(listOfPeople),
    selectedPeople: ko.observableArray([1])
};

    
ko.applyBindings(viewModel);

<ul data-bind="foreach: people">
    <li>
        <input type="checkbox" value="" data-bind="checkedValue: id, checked: $parent.selectedPeople"><span data-bind="text: name"></span>
    </li>
</ul>

<hr/>

<div data-bind="text: ko.toJSON($root)"></div>
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