How to get Url Referrer in ASP.NET Core

The StringValues class in ASP.NET Core is used to efficiently represent strings, particularly in the HttpContext object. To convert a StringValues instance to a regular string, you can simply call its ToString() method.

using Microsoft.AspNetCore.Mvc;

public class HomeController : Controller
{
    public IActionResult Index()
    {
        // Get the Referer (Referrer) header from the request
        var referrer = Request.Headers["Referer"].ToString();
        
        // Use the referrer URL as needed
        ViewData["Referrer"] = referrer;

        return View();
    }
}

The Referer header is optional. If the request doesn't include it (for example, when a user navigates directly to a page or if it has been stripped out for privacy reasons), the value will be an empty string.