如何在 asp.net 内核中获取项目的根目录。 Directory.GetCurrentDirectory() 在 Mac 上似乎无法正常工作

Question

My project has a folder structure to the tune of:

• Project,
• Project/data
• Project/Engine
• Project/Server
• project/front-end

In the server (running in the Project/Server folder) I refer to the folder like this:

var rootFolder = Directory.GetCurrentDirectory();
rootFolder = rootFolder.Substring(0,
            rootFolder.IndexOf(@"\Project\", StringComparison.Ordinal) + @"\Project\".Length);
PathToData = Path.GetFullPath(Path.Combine(rootFolder, "Data"));

var Parser = Parser();
var d = new FileStream(Path.Combine(PathToData, $"{dataFileName}.txt"), FileMode.Open);
var fs = new StreamReader(d, Encoding.UTF8);

On my windows machine this code works fine since Directory.GetCurrentDirectory() reffered to the current folder, and doing

rootFolder.Substring(0, rootFolder.IndexOf(@"\Project\", StringComparison.Ordinal) + @"\Project\".Length); 

gets me the root folder of the project (not the bin or debug folders). But when I ran it on a mac it got " Directory.GetCurrentDirectory() " sent me to /usr//[something else]. It didn't refer to the folder where my project lies.

What is the correct way to find relative paths in my project? Where should I store the data folder in a way that it is easily accessible to all the sub projects in the solution - specifically to the kestrel server project? I prefer to not have to store it in the wwwroot folder because the data folder is maintained by a different member in the team, and I just want to access the latest version. What are my options?

Answer 1

Depending on where you are in the kestrel pipeline - if you have access to IConfiguration ( Startup.cs constructor ) or IWebHostEnvironment ( formerly IHostingEnvironment ) you can either inject the IWebHostEnvironment into your constructor or just request the key from the configuration.

Inject IWebHostEnvironment in Startup.cs Constructor

public Startup(IConfiguration configuration, IWebHostEnvironment env)
{
     var contentRoot = env.ContentRootPath;
}

Using IConfiguration in Startup.cs Constructor

public Startup(IConfiguration configuration)
{
     var contentRoot = configuration.GetValue<string>(WebHostDefaults.ContentRootKey);
}

Answer 2

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

Answer 3

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);

Answer 4

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

Answer 5

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).

Answer 6

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;
}

Answer 7

I solved the problem with this code:

using System.IO;

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

Answer 8

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!

Answer 9

如果通过 DI 使用IWebHostEnvironment不适合您，请使用

AppContext.BaseDirectory

Answer 10

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);
}

Answer 11

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.Configuration.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.

Answer 12

It seems IHostingEnvironment has been replaced by IHostEnvironment (and a few others). You should be able to change the interface type in your code and everything will work as it used to :-)

You can find more information about the changes at this link on GitHub https://github.com/aspnet/AspNetCore/issues/7749

EDIT There is also an additional interface IWebHostEnvironment that can be used in ASP.NET Core applications. This is available in the Microsoft.AspNetCore.Hosting namespace.

Ref: https://stackoverflow.com/a/55602187/932448