Confirm prompt from controller

Question

I working with an Asp.Net Core web application, .Net 5, in a MVVM pattern.

I have a view page where a user specifies criteria to create a report and clicks Submit. The controller method then performs additional editing and finally checks to see if any records satisfy the criteria.

What I need is to be able to prompt the user if there are no records and have them confirm if a null report should be created.

I know I can't create the prompt from the controller, but I can't find a way to display a pop-up box to display the confirmation box and return the value. I've tried a number of things that I've found on the web, but none seem to work for me.

Can any provide an example?

Thanks