$root

This always refers to top level ViewModel. This makes it possible to access top level methods for manipulating ViewModel. This is usually the object, which is passed to ko.applyBindings.

$data

This property is lot like this keyword in Javascript object. $data property in a binding context refers to ViewModel object for the current context.

$index

This property contains index of a current item of an array inside a foreach loop. The value of $index will change automatically as and when the underlying Observable array is updated. Obviously, this context is available only for foreach bindings.

$parent

This property refers to parent ViewModel object. This is useful when you want to access outer ViewModel properties from inside of a nested loop.

$parentContext

The context object which is bound at the parent level is called $parentContext. This is different from $parent. $parent refers to data. Whereas, $parentContext refers to binding context. E.g. you might need to access the index of outer foreach item from an inner context.

$rawdata

This context holds raw ViewModel value in the current situation. This resembles $data but the difference is, if ViewModel is wrapped in Observable, then $data becomes just unwrapped. ViewModel and $rawdata becomes actual Observable data.

$component

This context is used to refer to ViewModel of that component, when you are inside a particular component. E.g. you might want to access some property from ViewModel instead of current data in the template section of component.

$componentTemplateNodes

This represents an array of DOM nodes passed to that particular component when you are within a specific component template.

To show or hide HTML DOM element depending on certain conditions.

To set the content of an HTML DOM element.

To set the HTML markup contents of a DOM element.

To apply CSS classes to an element.

To define the inline style attribute of an element.

To add attributes to an element dynamically.

In this binding, each array item is referenced in HTML markup in a loop.

If the condition is true, then the given HTML markup will be processed. Else, it will be removed from DOM.

Negation of If. If the condition is true, then the given HTML markup will be processed. Else, it will be removed from DOM.

This binding is used to bind the child elements of an object in the specified object’s context.

This binding is used to insert a component into DOM elements and pass the parameters optionally.

This binding is used to invoke a JavaScript function associated with a DOM element based on a click.

This binding is used to listen to the specified DOM events and call associated handler functions based on them.

This binding is used to invoke a JavaScript function when the associated DOM element is submitted.

This binding is used to enable certain DOM elements based on a specified condition.

This binding disables the associated DOM element when the parameter evaluates to true.

This binding is used to link respective DOM element’s value into ViewModel property.

This binding is used to create 2-way binding between text box or textarea and ViewModel property.

This binding is used to manually set the focus of a HTML DOM element through a ViewModel property.

This binding is used to create a link between a checkable form element and ViewModel property.

This binding is used to define the options for a select element.

This binding is used to work with elements which are selected currently in multi list select form control.

This binding is used to generate a unique name for a DOM element.