# Custom widgets

The standard approach to extending Sitefinity CMS frontend is to write custom widgets or to override the logic of the built-in ones. The corresponding elements for widgets in ASP.NET Core are `ViewComponents`. Thus, widgets that are available in the Sitefinity CMS Toolbox, correspond to the `ViewComponents` classes in the ASP.NET Core application.

The `ViewComponents` are useful in this scenario as they have a single method `InvokeAsync` that can render multiple views and can accept a range of arguments for configuration. This is similar to the existing Sitefinity ASP.NET MVC development model, where you create a `Controller` that has an `Index` action that can be invoked when the widget is rendered.

However, unlike the MVC Controllers, the `ViewComponents` do not have a `POST` action to handle `POST` requests.

Use the following video as a guideline for creating widgets:

 <iframe width="560" height="315" src="https://www.youtube.com/embed/G7Oy9Lz0VLo" frameborder="0" allow="accelerometer; encrypted-media; gyroscope; picture-in-picture" allowfullscreen=""></iframe>