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title Access HttpContext in ASP.NET Core
author coderandhiker
description Learn about using HttpContext in ASP.NET Core apps. HttpContext isn't thread-safe and can throw an exception when accessed.
monikerRange >= aspnetcore-3.1
ms.author tdykstra
ms.custom mvc
ms.date 04/23/2026
uid fundamentals/httpcontext

Access HttpContext in ASP.NET Core

[!INCLUDE]

The xref:Microsoft.AspNetCore.Http.HttpContext encapsulates all information about an individual HTTP request and response. An HttpContext instance is initialized when an HTTP request is received. The HttpContext instance is accessible by middleware and app frameworks such as Web API controllers, Razor Pages, SignalR, gRPC, and more.

For information about using HttpContext with an HTTP request and response, see xref:fundamentals/use-httpcontext.

Access HttpContext from Razor Pages

The Razor Pages xref:Microsoft.AspNetCore.Mvc.RazorPages.PageModel exposes the xref:Microsoft.AspNetCore.Mvc.RazorPages.PageModel.HttpContext property:

public class IndexModel : PageModel
{
    public void OnGet()
    {
        var message = HttpContext.Request.PathBase;

        // ...
    }
}

You can use the same property in the corresponding Razor Page View:

@page
@model IndexModel

@{
    var message = HttpContext.Request.PathBase;
    
    // ...
}

Access HttpContext from a Razor view in MVC

Razor views in the MVC pattern expose the HttpContext via the xref:Microsoft.AspNetCore.Mvc.Razor.RazorPage.Context%2A property on the view. The following example retrieves the current username in an intranet app by using Windows Authentication:

@{
    var username = Context.User.Identity.Name;
    
    // ...
}

Access HttpContext from a controller

Controllers expose the xref:Microsoft.AspNetCore.Mvc.ControllerBase.HttpContext%2A property:

public class HomeController : Controller
{
    public IActionResult About()
    {
        var pathBase = HttpContext.Request.PathBase;

        // ...

        return View();
    }
}

:::moniker range=">= aspnetcore-6.0"

Access HttpContext from Minimal APIs

To use HttpContext from Minimal APIs:

app.MapGet("/", (HttpContext context) => context.Response.WriteAsync("Hello World"));

:::moniker-end

Access HttpContext from middleware

To use HttpContext from custom middleware components, pass the HttpContext parameter into the Invoke or InvokeAsync method:

public class MyCustomMiddleware
{
    // ...

    public async Task InvokeAsync(HttpContext context)
    {
        // ...
    }
}

:::moniker range=">= aspnetcore-6.0"

Access HttpContext from SignalR

To use HttpContext from SignalR, call the xref:Microsoft.AspNetCore.SignalR.GetHttpContextExtensions.GetHttpContext%2A on the xref:Microsoft.AspNetCore.SignalR.Hub.Context%2A:

public class MyHub : Hub
{
    public async Task SendMessage()
    {
        var httpContext = Context.GetHttpContext();

        // ...
    }
}

Access HttpContext from gRPC methods

To use HttpContext from gRPC methods, see Resolve HttpContext in gRPC methods.

:::moniker-end

Access HttpContext from custom components

For other framework and custom components that require access to HttpContext, the recommended approach is to register a dependency by using the built-in Dependency Injection (DI) container. The DI container supplies the IHttpContextAccessor to any classes that declare it as a dependency in their constructors:

:::moniker range=">= aspnetcore-6.0"

var builder = WebApplication.CreateBuilder(args);

builder.Services.AddControllersWithViews();
builder.Services.AddHttpContextAccessor();
builder.Services.AddTransient<IUserRepository, UserRepository>();

:::moniker-end :::moniker range="< aspnetcore-6.0"

public void ConfigureServices(IServiceCollection services)
{
     services.AddControllersWithViews();
     services.AddHttpContextAccessor();
     services.AddTransient<IUserRepository, UserRepository>();
}

:::moniker-end

In the following example:

  • The UserRepository instance declares its dependency on IHttpContextAccessor.
  • The dependency is supplied when DI resolves the dependency chain and creates an instance of UserRepository.

:::moniker range=">= aspnetcore-6.0"

public class UserRepository : IUserRepository
{
    private readonly IHttpContextAccessor _httpContextAccessor;

    public UserRepository(IHttpContextAccessor httpContextAccessor) =>
        _httpContextAccessor = httpContextAccessor;

    public void LogCurrentUser()
    {
        var username = _httpContextAccessor.HttpContext.User.Identity.Name;
        
        // ...
    }
}

:::moniker-end :::moniker range="< aspnetcore-6.0"

public class UserRepository : IUserRepository
{
    private readonly IHttpContextAccessor _httpContextAccessor;

    public UserRepository(IHttpContextAccessor httpContextAccessor)
    {
        _httpContextAccessor = httpContextAccessor;
    }

    public void LogCurrentUser()
    {
        var username = _httpContextAccessor.HttpContext.User.Identity.Name;
        service.LogAccessRequest(username);
    }
}

:::moniker-end

Access HttpContext from a background thread

HttpContext isn't thread-safe. Reading or writing properties of the HttpContext outside of processing a request can result in a xref:System.NullReferenceException error.

Note

If your app generates sporadic NullReferenceException errors, review parts of the code that start background processing or code that continues processing after a request completes. Look for mistakes, such as defining a controller method as async void.

To safely do background work with HttpContext data:

  • Copy the required data during request processing.
  • Pass the copied data to a background task.
  • Don't reference HttpContext data in parallel tasks. Extract the data needed from the context before starting the parallel tasks.

To avoid unsafe code, never pass HttpContext into a method that does background work. Pass the required data instead.

:::moniker range=">= aspnetcore-6.0"

In the following example, the SendEmail method calls the SendEmailCoreAsync method to start sending an email. The value of the X-Correlation-Id header is passed to SendEmailCoreAsync instead of the HttpContext. Code execution doesn't wait for SendEmailCoreAsync to complete:

public class EmailController : Controller
{
    public IActionResult SendEmail(string email)
    {
        var correlationId = HttpContext.Request.Headers["X-Correlation-Id"].ToString();

        _ = SendEmailCoreAsync(correlationId);

        return View();
    }

    private async Task SendEmailCoreAsync(string correlationId)
    {
        // ...
    }
}

:::moniker-end :::moniker range="< aspnetcore-6.0"

In the following example, the SendEmailCore method is called to start sending an email. The correlationId parameter is passed to SendEmailCore, not the HttpContext. Code execution doesn't wait for SendEmailCore to complete:

public class EmailController : Controller
{
    public IActionResult SendEmail(string email)
    {
        var correlationId = HttpContext.Request.Headers["x-correlation-id"].ToString();

        _ = SendEmailCore(correlationId);

        return View();
    }

    private async Task SendEmailCore(string correlationId)
    {
        // ...
    }
}

:::moniker-end

Access IHttpContextAccessor or HttpContext in Razor components (Blazor)

If you want to access the IHttpContextAccessor or HttpContext in Razor components (Blazor apps), see xref:blazor/components/httpcontext.

Related content

  • Use HttpContext in ASP.NET Core
  • Razor Pages architecture and concepts in ASP.NET Core
  • gRPC services with ASP.NET Core