ASP.NET MVC Login ReturnUrl always NULL?

Question

Using Forms Authentication in ASP.NET MVC when trying to log back into a site, it puts a ReturnUrl parameter in the query string. My Logon action method accepts a \"returnU

Answer 1

Try the following:

        public static MvcForm BeginForm(this HtmlHelper htmlHelper, string id)
    {
        string formAction = htmlHelper.ViewContext.HttpContext.Request.RawUrl;

        TagBuilder tagBuilder = new TagBuilder("form");

        tagBuilder.MergeAttribute("id", id);
        tagBuilder.MergeAttribute("action", formAction);
        tagBuilder.MergeAttribute("method", HtmlHelper.GetFormMethodString(FormMethod.Post), true);

        HttpResponseBase httpResponse = htmlHelper.ViewContext.HttpContext.Response;
        httpResponse.Write(tagBuilder.ToString(TagRenderMode.StartTag));

        return new MvcForm(htmlHelper.ViewContext.HttpContext.Response);
    }

First ensure you have set the login url in the web.config, Next, ensure your Signin Form does not contain anything like action, for example:

View:

If you specify action you will always get null for return url:

Controller:

[AcceptVerbs(HttpVerbs.Post)]
public ActionResult SignIn(string userName, string password, bool? rememberMe, string returnUrl)
{
}