What am I doing wrong in ASP.NET

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 开发者_Python百科(are you missing a using directive or an assembly reference?)

Any help appreciated.

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 I recommend to use Web App project, not Web Site project (which is out-of-date)!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" %>

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

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.

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)