Question

I have a master page that set ups some variables that I want to use across the site..

protected void Page_Load(object sender, EventArgs e)
{
    //Get users name from AD
    str_DomainName = HttpContext.Current.User.Identity.Name;
    str_CurrentLogin = str_DomainName.Substring(5);

    //Display current user information
    DirectorySearcher search = new DirectorySearcher("LDAP://DCHS");
    search.Filter = String.Format("(SAMAccountName={0})", str_CurrentLogin);
    SearchResult result = search.FindOne();
    DirectoryEntry entry = result.GetDirectoryEntry();
    lbl_CurrentUser.Text = result.Properties["givenName"][0].ToString() + ' ' + result.Properties["sn"][0].ToString();

    // Get SID
    IntPtr logonToken = WindowsIdentity.GetCurrent().Token;
    WindowsIdentity windowsId = new WindowsIdentity(logonToken);

    //Set session variabls
    this.CurrentFirstName = result.Properties["givenName"][0].ToString();
    //this.CurrentEmail = result.Properties["mail"][0].ToString();
    //this.CurrentSID = windowsId.User.ToString();
    //this.CurrentUserName = str_CurrentLogin;
    //this.CurrentFullName = lbl_CurrentUser.Text;
    //this.CurrentDomain = str_DomainName;
    this.Session.Add("currentEmail", result.Properties["mail"][0].ToString());
}

public String CurrentFirstName
        {
            get { return (String)ViewState["currentFirstName"]; }
            set { ViewState["currentFirstName"] = value; }
        }

I then call them in my defalut.aspx page as follows:

protected void Page_PreRender(object sender, EventArgs e)
        {
            //try
            //{
                lbl_FullName.Text = Master.CurrentFullName;
                lbl_SID.Text = Master.CurrentSID;
                testLabel.Text = Master.CurrentEmail;
            //}
            //catch (Exception ex)
            //{ }
        }

This works fine.. If I however navigate away from the default page, then I get the following error..

Object reference not set to an instance of an object.

One the lbl_FullName.Text = Master.CurrentFullName; line

If I uncomment the try catch then it works fine, but I don’t believe that this is the correct method of avoiding the fault..

I’m only new to ASP, so be nice..

EDIT:

The variabes are being set in Master.cs as follows.

public String CurrentUserName
        {
            get { return (String)ViewState["currentUserName"]; }
            set { ViewState["currentUserName"] = value; }
        }

Answer 1

ViewState is per-page. When you navigate to the new page, it isn’t set.

Your master page should put these into Session instead.