How do I get the Web Root Path and the Content Root Path in ASP.NET Core?

Question

I am trying to add a root path as a parameter in a View, so I can pass it as a parameter to a PayPal button.

<form action="https://www.sandbox.paypal.com/cgi-bin/webscr" method="post" target="_top">
    ... snip ...

    <input type="hidden" name="return" value="@Model.UrlRoot/Manage/[email protected]">

    ... snip ...
</form>

I was sifting through the answers at How can I get my webapp's base URL in ASP.NET MVC? (20 answers) and ASP.NET MVC 6 application's virtual application root path

Since ASP.NET Core is quite different, the Request class no longer contains a .Url property, so most of those answers don't work.

Answer 1

You can inject the IHostingEnvironment into the Controller like this:

   public class HomeController : Controller
    {
        protected readonly IHostingEnvironment _hostingEnvironment;

        public HomeController(IHostingEnvironment hostingEnvironment)
        {

        }
    }

In your _ViewImports.cshtml add:

@using Microsoft.AspNetCore.Hosting
@inject IHostingEnvironment HostingEnvironment

Now you can use can use HostingEnvironment and all its properties in your form. For example HostingEnvironment.WebRootPath or HostingEnvironment.ContentRootPath

Answer 2

I came across Marius Schulz's post. (If you are Marius, please add your answer, contact me and I'll remove mine.)

https://blog.mariusschulz.com/2016/05/22/getting-the-web-root-path-and-the-content-root-path-in-asp-net-core

For some reason my Controllers don't have the IHostingEnvironment injected in the constructor, but they do have the Request object.

In my Controller, I've declared

var urlRoot = $"{Request.Scheme}://{Request.Host}{Url.Content("~")}";

and passed it to MyViewModel

var model = new MyViewModel { UrlRoot = urlRoot };
return View(model);

This takes into account http vs. https, port numbers, and hopefully, the site root if the web site is not rooted at /. Since my site is at / I cannot confirm that Url.Content("~") gets the site root.