How can I get my webapp's base URL in ASP.NET MVC?

Question

How can I quickly determine what the root URL is for my ASP.NET MVC application? I.e., if IIS is set to serve my application at http://example.com/foo/bar, then I'd like to be able to get that URL in a reliable way that doesn't involve getting the current URL from the request and chopping it up in some fragile way that breaks if I re-route my action.

The reason that I need the base URL is that this web application calls another one that needs the root to the caller web application for callback purposes.

Answer 1

Assuming you have a Request object available, you can use:

string.Format("{0}://{1}{2}", Request.Url.Scheme, Request.Url.Authority, Url.Content("~")); 

If it's not available, you can get to it via the context:

var request = HttpContext.Current.Request 

Answer 2

So none of the ones listed here worked for me, but using a few of the answers, I got something working:

public string GetBaseUrl() {     var request = HttpContext.Current.Request;     var appUrl = HttpRuntime.AppDomainAppVirtualPath;      if (appUrl != "/")          appUrl = "/" + appUrl;      var baseUrl = string.Format("{0}://{1}{2}", request.Url.Scheme, request.Url.Authority, appUrl);      return baseUrl; } 

Update for ASP.NET Core / MVC 6:

ASP.NET Core makes this process a bit more painful, especially if you are deep in your code. You have 2 options to get at the HttpContext

1) Pass it in from your controller:

var model = new MyClass(HttpContext); 

then in model:

private HttpContext currentContext;  public MyClass(HttpContext currentContext) {     this.currentContext = currentContext; } 

2) Perhaps the cleaner way is to inject it into your class, which starts with registering the types in your Startup:

public void ConfigureServices(IServiceCollection services) {     // Add framework services.     services.AddMvc();      services.AddTransient<MyClass, MyClass>();     services.TryAddSingleton<IHttpContextAccessor, HttpContextAccessor>(); } 

then have it injected for you like this:

private HttpContext currentContext;  public MyClass(IHttpContextAccessor httpContextAccessor) {     currentContext = httpContextAccessor.HttpContext; } 

in either case, here is the updated for .NET Core GetBaseUrl():

public string GetBaseUrl() {     var request = currentContext.Request;      var host = request.Host.ToUriComponent();      var pathBase = request.PathBase.ToUriComponent();      return $"{request.Scheme}://{host}{pathBase}"; }