Where is Request.IsAjaxRequest() in Asp.Net Core MVC?

Question

To learn more about the new exciting Asp.Net-5 framework, I'm trying to build a web application using the newly released Visual Studio 2015 CTP-6.

Most things looks really promising, but I can't seem to find Request.IsAjaxRequest() - a functionality I've been using quite frequently on older MVC projects.

Is there a better way to do this - that made them remove this method - or is it "hidden" somewhere else?

Thanks for any advice on where to find it or what to do instead!

Solution 1

I got a little confused, because the title mentioned MVC 5.

Search for Ajax in the MVC6 github repo doesn't give any relevant results, but you can add the extension yourself. Decompilation from MVC5 project gives pretty straightforward piece of code:

/// <summary>
/// Determines whether the specified HTTP request is an AJAX request.
/// </summary>
/// 
/// <returns>
/// true if the specified HTTP request is an AJAX request; otherwise, false.
/// </returns>
/// <param name="request">The HTTP request.</param><exception cref="T:System.ArgumentNullException">The <paramref name="request"/> parameter is null (Nothing in Visual Basic).</exception>
public static bool IsAjaxRequest(this HttpRequestBase request)
{
  if (request == null)
    throw new ArgumentNullException(nameof(request));
  if (request["X-Requested-With"] == "XMLHttpRequest")
    return true;
  if (request.Headers != null)
    return request.Headers["X-Requested-With"] == "XMLHttpRequest";
  return false;
}

Since MVC6 Controller seems to be using Microsoft.AspNet.Http.HttpRequest, you'd have to check request.Headers collection for appropriate header by introducing few adjustments to MVC5 version:

/// <summary>
/// Determines whether the specified HTTP request is an AJAX request.
/// </summary>
/// 
/// <returns>
/// true if the specified HTTP request is an AJAX request; otherwise, false.
/// </returns>
/// <param name="request">The HTTP request.</param><exception cref="T:System.ArgumentNullException">The <paramref name="request"/> parameter is null (Nothing in Visual Basic).</exception>
public static bool IsAjaxRequest(this HttpRequest request)
{
  if (request == null)
    throw new ArgumentNullException(nameof(request));

  if (request.Headers != null)
    return request.Headers["X-Requested-With"] == "XMLHttpRequest";
  return false;
}

or directly:

var isAjax = request.Headers["X-Requested-With"] == "XMLHttpRequest"

Solution 2

in asp.net core, You can use Context.Request.Headers.

bool isAjaxCall = Context.Request.Headers["x-requested-with"]=="XMLHttpRequest";

Solution 3

For those who are working on ASP.Net Core

HttpContext.Request.Headers["X-Requested-With"] == "XMLHttpRequest";

Example
Controller.cs

bool isAjax = HttpContext.Request.Headers["X-Requested-With"] == "XMLHttpRequest";

if (isAjax)
   return Json(new { redirectTo = Url.Action("Index", "ControllerAction") });
else
   return RedirectToAction("Index", "ControllerAction");

Solution 4

After using the solution provided above by Patryk Ćwiek above I noticed a potential issue (largely due to my incorrectly typing "XMLHttpRequest" as "XmlHttpRequest"), which resulted in an incorrect return value. To accommodate my mistake, I updated it slightly. Here's my updated version:

    public static bool IsAjaxRequest(this HttpRequest request)
    {
        if (request == null)
            throw new ArgumentNullException(nameof(request));

        if (request.Headers != null)
            return !string.IsNullOrEmpty(request.Headers["X-Requested-With"]) &&
                string.Equals(
                    request.Headers["X-Requested-With"], 
                    "XmlHttpRequest", 
                    StringComparison.OrdinalIgnoreCase);

        return false;
    }

View more solutions

Comments

[Patryk Ćwiek]

As far as I can tell, it's still there. It's an extension method in System.Web.Mvc, class AjaxRequestExtensions. That's for MVC5, I don't know about MVC6...

[Chris Pratt]

That's what the OP is asking about: MVC6. Of course it's still there in MVC5.

[mikal]

@PatrykĆwiek Ok, yes, I'm testing MVC6. I might be wrong of course, but it seems to be missing from the "Microsoft.AspNet.Mvc": "6.0.0-beta3" package - or any of the other standard mvc-6 packages that comes with a new mvc-6 project.

[Chris Pratt]

Not sure about this but try just: IsAjaxRequest(), without the Request. prefix.

[mikal]

For a temporary solution on this, I decided to copy and modify the method from System.Web.Mvc.AjaxRequestExtensions. Hope it helps others, until this finds it way to the framework. public static class AjaxRequestExtensions { public static bool IsAjaxRequest(this HttpRequest request) { if (request == null) { throw new ArgumentNullException("request"); } return request.Headers != null && request.Headers["X-Requested-With"] == "XMLHttpRequest"; } }

[zmechanic]

I think someone need to edit this question and change MVC5 to MVC6 in title.

[Fred]

The source code from the version of MVC5 is here: github.com/ASP-NET-MVC/aspnetwebstack/blob/master/src/…

[Muflix]

what is namespace for Context ?

[Robert Slaney]

@Aligned No, there is nothing in the fetch spec about adding an identifier in the request headers. The X-Requested-With isn't in the XMLHttpRequest spec either ( hence the "X-" prefix), but all the vendors added it as a convention. There is no indication any convention will done for fetch. If your system needs to know then you need to manually add a header when creating your fetch request