myViewModel.fullName('Joe Smith').age(50)

<div> First name: <span data-bind="text: firstName"></span></div>
<div> Last name: <span data-bind="text: lastName"></span></div>
<div class="heading">Hello, <input data-bind="textInput: fullName"/><div>function MyViewModel(){this.firstName = ko.observable('Planet');this.lastName = ko.observable(‘Earth'); this.fullName = ko.pureComputed({ read: function(){ return this.firstName() + " " + this.lastName(); }, write: function(value){ var lastSpcePos = value.lastIndexOf(" "); if （lastSpacePos > 0）{ this.firstName(value.substring(0, lastSpacePos)); this.lastName(value.substring(lastSpacePos + 1)); } }, owner: this }) } ko.applyBindings(new MyViewModel());

<div class="heading"><input type="checkbox" data-bind="checked: selectedAllProduce" title="Select all/none"/> Produce
</div>
<div data-bind="foreach: produce"><label><input type="checkbox" data-bind="checkedValue: $data, checked: $parent.selectedProduce"/><span data-bind="text: $data"></span></label>
</div>function MyViewModel() {this.produce = [ 'Apple', 'Banana', 'Celery', 'Corn', 'Orange', 'Spinach' ];this.selectedProduce = ko.observableArray([ 'Corn', 'Orange' ]); this.selectedAllProduce = ko.pureComputed({ read: function () { // Comparing length is quick and is accurate if only items from the // main array are added to the selected array. return this.selectedProduce().length === this.produce.length; }, write: function (value) { this.selectedProduce(value ? this.produce.slice(0) : []); }, owner: this }); } ko.applyBindings(new MyViewModel());

<div>Enter bid price: <input data-bind="textInput: formattedPrice"/></div>
<div>(Raw value: <span data-bind="text: price"></span>)</div>function MyViewModel() {this.price = ko.observable(25.99);this.formattedPrice = ko.pureComputed({read: function() {return '$' + this.price().toFixed(2);}，write: function(value) {value = parseFloat(value.replace(/[^\.\d]/g, ""));this.price(isNaN(value) ? 0 : value);},})
}ko.applyBindings(new MyViewModel());

<div>Enter a numeric value: <input data-bind="textInput: attemptedValue"/></div>
<div class="error" data-bind="visible: !lastInputWasValid()">That's not a number!</div>
<div>(Accepted value: <span data-bind="text: acceptedNumericValue"></span>)</div>function MyViewModel() {this.acceptedNumbericValue = ko.observable(123);this.lastInputWasValid = ko.observble(true);this.attemptedValue = ko.pureComputed({read: this.acceptedNumbericValue,write: function (value) {if (isNaN(value))this.lastInputWasValid(false);else {this.lastInputWasValid(true);this.acceptedNumbericValue(value);}},owner: this});
}ko.applyBindings(new MyViewModel());