Create an MVC component for the UI

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

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

Add a Controller and annotate it with an IframeComponent attribute.

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

Add a 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>