Question

@using (Ajax.BeginForm("Login", "Account", "", 
            new AjaxOptions { HttpMethod = "POST" }, 
            new { id = "loginForm", name = "loginForm" }))
{
 ...
}

This form perform a request and receive a response 200 OK. Debbuging I can see the response html but I don´t get redirected.

If I do it manually without using html helps I get successfully redirected to where I need to.

This is the controller:

//
    // POST: /Account/Login
    [HttpPost]        
    [AllowAnonymous]
    [ValidateAntiForgeryToken]
    public ActionResult Login(LoginModel model)
    {
        MembershipProvider mp = Membership.Provider;
        bool isDigital = bool.Parse(Request.Form.GetValues("hasDigital")[0]);
        string certDBNumber;

        if (isDigital)
        {
            /*** Retira só o que enteressa do Certificado.Subject (CPF/CNPJ)*/
            string code = Request.Form.GetValues("code")[0];
            string[] dataArray = code.Split(',');
            string data = dataArray.Last();
            string[] numberArr = data.Split(':');
            string number = numberArr.Last();

            /*** Resgata chave do usuário no banco ***/
            using (tgpwebgedEntities context = new tgpwebgedEntities())
            {
                var userObj = from u in context.aspnet_Users 
                              where u.UserName == model.UserName 
                              select u.UserId;
                Guid userID = userObj.First();
                var obj = from u in context.sistema_UsersCertified 
                          where u.userID == userID select u.keyNumber;
                certDBNumber = obj.First();
            }

            //Verifica se usuário é credenciado
            if (number == certDBNumber) {
                FormsAuthentication.SetAuthCookie(model.UserName, false);
                return RedirectToAction("Index", "Home");                    
            }
        }//Login sem certificado digital
        else
        {
            if (ModelState.IsValid && 
                           mp.ValidateUser(model.UserName, model.Password))
            {
                FormsAuthentication.SetAuthCookie(model.UserName, false);
                return RedirectToAction("Index", "Home");
            }
        }
        /*** Se chegou até aqui algo deu errado. Mostra denovo o form ***/
        ModelState.AddModelError("", "Username ou Password incorreto!.");
        return View(model);
    }

Why this strange behavior?

Answer 1

As a result of this being an ajax post, you cannot redirect. An option would be to return a value such that the success function realized the redirection needed to take place, and then issued

if( someReturnedFlag == true ){
 window.location = redirectionUrl;//http://www.stackoverflow.com
}

Alternatively, you could make a redirection view

RedirectionView.cshtml

@{
 Layout = null;
}
<script type="text/javascript">
 window.location = "hardcodedurl";//or pass it in using @model
</script>

And then return this view from your ajax post and it would redirect.

---

Edit

This got more attention than I expected, so I thought I would improve this answer a little bit with two more complete examples.

---

1: jQuery’s ajax

view:

$.ajax({
        url: "@(Url.Action("TargetAction","TargetController"))",
        type: 'POST',
        data: $("#loginForm").serialize(),
        success: function (URL) {
         window.location = URL;
        }
});

controller:

public class TargetController: Controller
[HttpPost]
public string TargetAction(ViewModel model)
{
 //use model (note that the serialized form was bound to the model)
 return "http://www.stackoverflow.com";
}

---

2: RedirectionView.cshtml

main view:

@{
 AjaxOptions ajaxOpts = new AjaxOptions
 {
    UpdateTargetId = "redirectWhenDone"
 };
}

@using (Ajax.BeginForm("TargetAction", ajaxOpts))
{
 ...
}
<div id="redirectWhenDone"></div>

RedirectionView.cshtml

@model string
@{
 Layout = null;
}
<script type="text/javascript">
 window.location = "@(Model)";
</script>

Controller

[HttpPost]
public ActionResult TargetAction(ViewModel vm)
{
 //use ViewModel

 ...


 //it is important to use an object here for the string
 object url = "http://www.stackoverflow.com";
 //otherwise the View() method will consider the string a parent location and look
 //for the RedirectionView in the wrong place (basically using the wrong overload)
 return View("RedirectionView", url );
}