MVC - 401 Unauthorization redirect page

Sometimes we need to redirect our pages to some specific path when 401 unauthorized error happen. But by default it will redirect to some predefined path (Ex: ../login.aspx?ReturnUrl=home/index) and it may go 404 error if not found in our project.

To customize this default redirect path, i went through many ways and finally found simple change is

<authentication mode="Forms">

      <forms timeout="60" loginUrl="~/" />

</authentication>

Note: In browser network tab we cannot see 401 (Unauthorized) error, it will show as 302 (Redirect found). To resolve this, we can customize application end request method in global.asax file like below, But it will not redirect to login page instead it will show error page.

void Application_EndRequest(object sender, EventArgs e)

{

    if (Context.Response.StatusCode == 302)

    {

        Context.Response.Clear();

        Context.Response.StatusCode = 401;

    }

}

MVC - How to get current domain root path in javaScript variable

Problem statement:

Get current domain root path in javascript variable. In some cases, we want to redirect to domain root from client side. Below is the solution for that.

Solution:

Create property in MVC model class to return current domain (Getting this in client side may occurs some url mismatches)

public class LocalMVCModel

    {

        ...etc., your other properities

        public string CurrentDomain { get { return GetSiteRoot(); } }

        private string GetSiteRoot()

        {

            string port = System.Web.HttpContext.Current.Request.ServerVariables["SERVER_PORT"];

            if (port == null || port == "80" || port == "443")

                port = "";

            else

                port = ":" + port;

            string protocol = System.Web.HttpContext.Current.Request.ServerVariables["SERVER_PORT_SECURE"];

            if (protocol == null || protocol == "0")

                protocol = "http://";

            else

                protocol = "https://";

            string sOut = protocol + System.Web.HttpContext.Current.Request.ServerVariables["SERVER_NAME"] + port + System.Web.HttpContext.Current.Request.ApplicationPath;

            if (sOut.EndsWith("/"))

            {

                sOut = sOut.Substring(0, sOut.Length - 1);

            }

            return sOut;

        }

        ...etc., your other properities

}

Get this property in any cshtml page as below in layout.cshtml page or in any global page

@model your.namespace.LocalMVCModel

<script type="text/javascript">

   currentDomain = '@(Model.CurrentDomain)';

</script>

or simply

<script type="text/javascript">

   currentDomain = '@(Url.Content("~"))';

</script>

 Notes:
- Razor syntax @ cannot be accessed in *.js files, so add script in cshtml page itself preferrably in layout page or some global page.

- Single quote required for razor syntax to consider as string
- Variable currentDomain in javascript can be declared anywhere in JS files and accessed here.