How to get root directory of project in asp.net core. Directory.GetCurrentDirectory() doesn't seem to work correctly on a mac

Working on .Net Core 2.2 and 3.0 as of now.

To get the projects root directory within a Controller:

• Create a property for the hosting environment

  private readonly IHostingEnvironment _hostingEnvironment;
  

• Add Microsoft.AspNetCore.Hosting to your controller

  using Microsoft.AspNetCore.Hosting;
  

• Register the service in the constructor

  public HomeController(IHostingEnvironment hostingEnvironment) {
      _hostingEnvironment = hostingEnvironment;
  }
  

• Now, to get the projects root path

  string projectRootPath = _hostingEnvironment.ContentRootPath;
  

To get the "wwwroot" path, use

_hostingEnvironment.WebRootPath

In some cases _hostingEnvironment.ContentRootPath and System.IO.Directory.GetCurrentDirectory() targets to source directory. Here is bug about it.

The solution proposed there helped me

Path.GetDirectoryName(Assembly.GetEntryAssembly().Location);

If you are using ASP.NET MVC Core 3 or newer, IHostingEnvironment has been deprecated and replaced with IWebHostEnvironment

public Startup(IWebHostEnvironment webHostEnvironment)
{
    var webRootPath = webHostEnvironment.WebRootPath;
}

As previously answered (and retracted). To get the base directory, as in the location of the running assembly, don't use Directory.GetCurrentDirectory(), rather get it from IHostingEnvironment.ContentRootPath.

private IHostingEnvironment _hostingEnvironment;
    private string projectRootFolder;
    public Program(IHostingEnvironment env)
    {
        _hostingEnvironment = env;
        projectRootFolder = env.ContentRootPath.Substring(0,
            env.ContentRootPath.LastIndexOf(@"\ProjectRoot\", StringComparison.Ordinal) + @"\ProjectRoot\".Length);
    }

However I made an additional error: I had set the ContentRoot Directory to Directory.GetCurrentDirectory() at startup undermining the default value which I had so desired! Here I commented out the offending line:

 public static void Main(string[] args)
    {
        var host = new WebHostBuilder().UseKestrel()
           // .UseContentRoot(Directory.GetCurrentDirectory()) //<== The mistake
            .UseIISIntegration()
            .UseStartup<Program>()
            .Build();
        host.Run();
    }

Now it runs correctly - I can now navigate to sub folders of my projects root with:

var pathToData = Path.GetFullPath(Path.Combine(projectRootFolder, "data"));

I realised my mistake by reading BaseDirectory vs. Current Directory and @CodeNotFound founds answer (which was retracted because it didn't work because of the above mistake) which basically can be found here: Getting WebRoot Path and Content Root Path in Asp.net Core

Try looking here: Best way to get application folder path

To quote from there:

System.IO.Directory.GetCurrentDirectory() returns the current directory, which may or may not be the folder where the application is located. The same goes for Environment.CurrentDirectory. In case you are using this in a DLL file, it will return the path of where the process is running (this is especially true in ASP.NET).

I solved the problem with this code:

using System.IO;

var path = Path.GetDirectoryName(Assembly.GetEntryAssembly().Location.Substring(0, Assembly.GetEntryAssembly().Location.IndexOf("bin\\")))

I test and compare on asp.net core 6, I think this can help someone.

Assume your project location path is D:\Project\Server, if you use linux or mac just replace \ to /.

var app = builder.Build();
IWebHostEnvironment environment = app.Environment;

System.Console.WriteLine(environment.ContentRootPath);
// D:\Project\Server\
System.Console.WriteLine(environment.WebRootPath);
// D:\Project\Server\wwwroot

System.Console.WriteLine(Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location));
// D:\Project\Server\bin\Debug\net6.0
System.Console.WriteLine(Path.GetDirectoryName(Assembly.GetExecutingAssembly().GetName().CodeBase));
// file:\D:\Project\Server\bin\Debug\net6.0
System.Console.WriteLine(Path.GetDirectoryName(Assembly.GetEntryAssembly().Location));
// D:\Project\Server\bin\Debug\net6.0

System.Console.WriteLine(Directory.GetCurrentDirectory());
// D:\Project\Server
System.Console.WriteLine(AppDomain.CurrentDomain.BaseDirectory);
// D:\Project\Server\bin\Debug\net6.0\
System.Console.WriteLine(AppContext.BaseDirectory);
// D:\Project\Server\bin\Debug\net6.0\

Note: If environment.WebRootPath is empty string, you need create wwwroot folder in root project, then everything work fine.

If using the IWebHostEnvironment via DI is not an option for you, use

AppContext.BaseDirectory

If that can be useful to anyone, in a Razor Page cshtml.cs file, here is how to get it: add an IHostEnvironment hostEnvironment parameter to the constructor and it will be injected automatically:

public class IndexModel : PageModel
{
    private readonly ILogger<IndexModel> _logger;
    private readonly IHostEnvironment _hostEnvironment;

    public IndexModel(ILogger<IndexModel> logger, IHostEnvironment hostEnvironment)
    {
        _logger = logger;
        _hostEnvironment = hostEnvironment; // has ContentRootPath property
    }

    public void OnGet()
    {

    }
}

PS: IHostEnvironment is in Microsoft.Extensions.Hosting namespace, in Microsoft.Extensions.Hosting.Abstractions.dll ... what a mess!

namespace app.Controllers;

public class TestController: Controller
{

  private readonly IHostEnvironment _env;
  private readonly string _rootPath;

  public ProductController(IHostEnvironment env)
  {
    _env = env;
    _rootPath = _env.ContentRootPath;
  }

}

Here IHostingEnvironment env this parameter will be passed to the controller's constructor method, that env is similar to the process.env in nodejs

So, we are storing that env to our controller property _env [Note: _ is used because this is a convention or good practice for private class properties]

Now we have a property ContentRootPath: string in that _env variable that returns the absolute path to the root directory where your dotnet mvc is stored.

So, now we are storing that path to another string variable _rootPath

_rootPath = _env.ContentRootPath

Some of you maybe familiar with this.something but in C# using this is not required

Based on Henrique A technique and supports Unit Test contexts as well...

ReadOnlySpan<char> appPath = Assembly.GetEntryAssembly().Location.Replace("YOURTestProject", "YOUR");
var dir = Path.GetDirectoryName(appPath.Slice(0, appPath.IndexOf("bin\\")));
string path = Path.Combine(dir.ToString(), "Resources", "countries.dat");
if (System.IO.File.Exists(path))
{
    countries = System.IO.File.ReadAllLines(path);
}

Asp.net 6.0

program.cs

IWebHostEnvironment environment = builder.Environment;
environment.ContentRootPath = AppDomain.CurrentDomain.BaseDirectory; // <-- output: *\ProjectName\bin\Debug\net6.0\

In Home controller

    private readonly IWebHostEnvironment _webHostEnvironment;

    public HomeController(IWebHostEnvironment webHostEnvironment)
    {
        _webHostEnvironment = webHostEnvironment;

        string fullPath = _webHostEnvironment.ContentRootPath;
    }

Used within a ASP.NET Core Blazor Project:

In Program.cs:

var builder = WebApplication.CreateBuilder(args);

With Console.WriteLine($"Content root path: {builder.Environment.ContentRootPath}."); you can show the default configuration for the content root path of the builder environment.

I fixed it by just setting the "Working directory" in rider's debug configuration.