Create MVC component

The Optimizely Content Management System (CMS) extension of the IFrameComponent has the following additional parameters:

UrlFromUtil – Optional. The URL to the source, relative to the Utils folder. Used instead of Url property.
UrlFromUi – Optional. The URL to the source, relative to the UI folder. Used instead of Url property.

First, add a controller. Annotate the controller with an IframeComponent attribute.

[IFrameComponent(Url = "/helloworld", Title = "Hello World Component", Categories = "content")]
public class HelloWorldController: Controller {
  public ActionResult Index() {
    return View();
  }
}

Then add an Index.cshtml view to the Views/HelloWorld directory:

@{
   Layout = null;
}
    
<!DOCTYPE html>
<html>
  <head>
    <meta name="viewport" content="width=device-width" />
    <title>HelloWorld</title>
  </head>
  <body>
    <div>
      <div>Hello World</div>
    </div>
  </body>
</html>