Difference between 4 statements - PLease Explain

Hi..

For Single Sign On,

I am using statement -

"Page.User.Identity.Name" to get the User Name,

Changed the iis setting - Windows Authentication Enabled = true;
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My Requirement -
1. I have given a set of users (25 for now), i.e. 25 windows users.
2. My Single Sign On Portal is for these 25 users only.
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My Query -
1. I have written the following code on Page_Load event -
 if(Page.Ispostback == false )
{
  string user =  Page.User.Identity.Name.Trim(); //IN//abc.xyz
  string checkUser = user.Substring(3).ToString().Trim();//abc.xyz

  if (checkUser is present in the database)
  {
  Response.Redirect("Index.aspx",false);
 }
  else
  {
  Response.Redirect ("Errorpage.aspx",false);
 }
}
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Error-
Sometimes, even if the user is valid, the system redirects to error page.

When I removed the POstBack Condition - then system redirects to Index Page.

Now, Postback will be false on page_load everytime.

It works fine on local. But, it gives error on server.

Please give me some ways to detect issues on server....

--------

How to detect this issue?? What should I do ??

Do I need to use any other thing to implement Single Sign ON

PLease guide and explain...

for 2nd point:
basicaly you need to enable Integrated windows authentication and the use the following:

string strName = HttpContext.Current.User.Identity.Name.ToString();

you still have other methods to get the logged in user name.



Now for 3. System.Security.Principal.WindowsIdentity.GetCurrent().Name.ToString();

You will need to configure the application to impersonate the Windows  user who is accessing it by adding the following element after the  authentication element in the Web.Config:

For Example

void Authenticate() {     string strLogin = null;      try     {         strLogin = System.Security.Principal.WindowsIdentity.GetCurrent().Name;         Session.Add("Login", strLogin);            }     catch (Exception ex)     {            }
}


For 4.System.Environment.UserName;
Gets the user name of the person who is currently 
logged on to the Windows operating system.

For Example:
public static void Main()     {     Console.WriteLine(); //  <-- Keep this information secure! -->     Console.WriteLine("UserName: {0}", Environment.UserName);     }

Hi budy,

for your 1st Point.
Page.User.Identity.Name
this wil check the key value which has been given in the webconfig as given below.


   <deny users="me" />
 
 for example if you checking the  authentication for page user.

public partial class Login : Page {     protected void Page_Load(object sender, EventArgs e)     {       }     protected void LoggedIn(object sender, EventArgs e)     {         //This is redirect the user to their page         switch (Page.User.Identity.Name.ToLower())         {             case "me":                 Response.Redirect("~/me.aspx");                 break;             case "you":                 Response.Redirect("~/you.aspx");                 break;             case "them":                 Response.Redirect("~/them.aspx");                 break;         }     }     protected void Unnamed6_Click(object sender, EventArgs e)     {      } }


More more details go this link:
http://stackoverflow.com/questions/20843573/using-page-user-identity-name-in-login-page