What am I doing wrong in ASP.NET - asp.net

Question

Here is my master page code behind:
namespace mysite.MasterPages
{
public partial class Main : System.Web.UI.MasterPage
{
public bool isLoggedIn;
protected void Page_Load(object sender, EventArgs e)
{
isLoggedIn = Request.IsAuthenticated; // Is the user currently logged in
}
}
}
Here is my register page code behind:
namespace mysite
{
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if (((MasterPage)Page.Master).isLoggedIn)
{
Response.Redirect("default.aspx");
}
}
}
}
I'm trying to make the isloggedIn accessible to all pages using that as a master page! I get errors like:
Error 2 The name 'isLoggedIn' does not exist in the current context
Error 3 'System.Web.UI.MasterPage' does not contain a definition for 'isLoggedIn' and no extension method 'isLoggedIn' accepting a first argument of type 'System.Web.UI.MasterPage' could be found (are you missing a using directive or an assembly reference?)
Any help appreciated.

Answer 1

add <%# MasterType VirtualPath="~/Main.master" %> to your page markup.
and your this.Master's type becomes AlphaPack.MasterPages.Main instead of System.Web.UI.MasterPage. So you will be able to access it without cast:
this.Master.IsLoggednIn
Currently you need do next:
((AlphaPack.MasterPages.Main)this.Master).isLoggednIn
And better - create a property. And hold data not in variable but in ViewState (read Control State vs. View State):
namespace AlphaPack.MasterPages
{
public partial class Main : System.Web.UI.MasterPage
{
protected void Page_Load(object sender, EventArgs e)
{
this.IsLoggedIn = Request.IsAuthenticated;
}
public bool IsLoggedIn
{
get { return this.ViewState["isLoggedIn"] as bool? ?? false; }
set { this.ViewState["isLoggedIn"] = value; }
}
}
}
And what about code-behind. I recommend to use Web App project, not Web Site project (which is out-of-date)!
Next markup syntax is used. Web app:
<%# Page Language="C#" AutoEventWireup="true" CodeBehind="MyPage.aspx.cs" Inherits="MyNamespace.MyPage" MasterPageFile="~/MyMaster.master" Title="MyTitile" %>
and web site:
<%# Page Language="C#" AutoEventWireup="true" CodeFile="MyPage.aspx.cs" Inherits="MyPage" MasterPageFile="~/MyMaster.master" Title="MyTitile" %>

Answer 2

if (((MasterPage)Page.Master).isLoggedIn)
Should be
if (((mysite.MasterPages.Main)Page.Master).isLoggedIn)
You cast Master to a MasterPage type (which is useless as it is already a MasterPage). But MasterPage doesn't contain the property isLoggedIn. That's why you can't access it.
So, just cast the Master property to the right type, in your case mysite.MasterPages.Main

Answer 3

The problem here is that your are declaring isLoggedIn within an inline code-block, so it will only be scoped to within that block.
You'll need to add it as a variable within the code-behind class or within <script runat="server"></script> tags, if adding the server-side code inline, i.e. (trimmed down for brevity):
<script runat="server">
public bool IsLoggedIn;
protected void Page_Load(object sender, EventArgs e)
{
IsLoggedIn = Request.IsAuthenticated;
}
</script>
You could then access the master page in subpages like so:
<%
if (((MasterPage)Page.Master).IsLoggedIn)
{
}
%>
However, I'm not sure that this is the best way to achieve what you want. I would probably take that logic out of the master page and stick it in a purpose built authentication class or service.

Answer 4

Usually one would store such Global 'states' inside a session variable. Are passing it around as a query string parameter?
And why are you not putting the code in the code behind?
Edit 1:
Just move this logic:
Response.Redirect("default.aspx");
directly into your masterpage:
protected void Page_Load(object sender, EventArgs e)
{
if (Request.IsAuthenticated) // Is the user currently logged in
{
Response.Redirect("default.aspx");
}
}
If this is the default behaviour you want for all pages that will be using this Master Page.
Edit 2:
you said in a comment :
and how would i go about accessing the
variable on other pages?
There are 3 ways I can think of:
Query String (Per Page Request)
ViewState (Per Page)
Session Variable (Available Globally)