Reactivity

Reactivity is a system at the core of the Lightning Web Components framework. The framework observes changes to the values of fields and properties. When it observes a change, it reacts. It reevaluates all the expressions used in the template and rerenders the component, which displays the new values.

Public properties in a component template are reactive. In a component's JavaScript class, If a field’s value changes, and the field is used in a template or in a getter of a property that’s used in a template, the component rerenders and displays the new value. If a field is assigned an object or an array, the framework observes some changes to the internals of the object or array, such as when you assign a new value.

For more information, see:

• Reactivity for public properties
• Reactivity for Fields, Objects, and Arrays

See Also

• Run Code When a Component Renders