What are the advantages of using the ASP.NET formView control?

This type of ASP.NET control gives you a certain "agility" for building forms for editing, creating, and viewing data. It may seem advantageous if we take into account all its support for a basic CRUD (create, read, update, delete), but its customization will demand mastery over the component, where a simple DataSource exchange will require a small study (try using it) and you will see that this effort was not worth it.

I would recommend you to create your own html and tailor your need, but look at this DevMedia article that covers creating a customer sign-in screen: link