How to show logged In user related task in dropdown list

Question

I am working on a project which contains a master page. On that master page, I have buttons (Home, About) and Login drop-down control. After login I want to show login username in dropdown list control and log out at the same time.

Register user

   string cs = ConfigurationManager.ConnectionStrings["DBCS"].ConnectionString;

    using (SqlConnection con = new SqlConnection(cs))
    {
        SqlCommand cmd = new SqlCommand("spRegisterUser", con);
        cmd.CommandType = CommandType.StoredProcedure;

        SqlParameter Name = new SqlParameter("@Name", txtName.Text);
        SqlParameter Email = new SqlParameter("@Email", txtEmail.Text);
        string encryptedPassword = FormsAuthentication.HashPasswordForStoringInConfigFile(txtPassword.Text, "SHA1");
        SqlParameter password = new SqlParameter("@Password", encryptedPassword);
        SqlParameter Mobile = new SqlParameter("@MobileNo", txtMobile.Text);

        cmd.Parameters.Add(Name);
        cmd.Parameters.Add(Email);
        cmd.Parameters.Add(password);
        cmd.Parameters.Add(Mobile);

        con.Open();
        int ReturnCode = (int)cmd.ExecuteScalar();

        if (ReturnCode == -1)
        {
            lblmessage.ForeColor = System.Drawing.Color.Red;
            lblmessage.Text = "Email Already In Use";
        }
        else
        {
            SendEmail();   
            Response.Redirect("https://localhost/JustEat.com/Login.aspx");
        }
 }

dropdown list Control at Home.Master

<asp:DropDownList ID="ddlLogin" CssClass="btn" runat="server" 
AutoPostBack="True" OnSelectedIndexChanged="ddlLogin_SelectedIndexChanged">
                    <asp:ListItem Value="-1">User</asp:ListItem>
                    <asp:ListItem Value="1">SignUp</asp:ListItem>
                    <asp:ListItem Value="2">Login</asp:ListItem>

                </asp:DropDownList>

Home.Master.aspx.cs

protected void ddlLogin_SelectedIndexChanged(object sender, EventArgs e)
    {
        if (ddlLogin.SelectedValue == "-1")
        {

        }
        else if (ddlLogin.SelectedValue == "1")
        {
            Response.Redirect("https://localhost/JustEat.com/Signup.aspx");
        }
        else if (ddlLogin.SelectedValue == "2")
        {
            Response.Redirect("https://localhost/JustEat.com/Login.aspx");
        }
    }

Method to Authenticate User

private bool AuthenticateUser(string username, string password)
    {

        string CS = ConfigurationManager.ConnectionStrings["DBCS"].ConnectionString;

        using (SqlConnection con = new SqlConnection(CS))
        {
            SqlCommand cmd = new SqlCommand("spAuthenticateUser", con);
            cmd.CommandType = CommandType.StoredProcedure;


            string EncryptedPassword = FormsAuthentication.HashPasswordForStoringInConfigFile(password, "SHA1");

            SqlParameter paramEmail = new SqlParameter("@Email", username);
            SqlParameter paramPassword = new SqlParameter("@Password", EncryptedPassword);

            cmd.Parameters.Add(paramEmail);
            cmd.Parameters.Add(paramPassword);

            con.Open();
            int ReturnCode = (int)cmd.ExecuteScalar();
            return ReturnCode == 1;
        }
    }

Login Button Click Event

if (AuthenticateUser(txtEmail.Text, txtPassword.Text))
        {
            Session["UserName"] = txtEmail.Text;
            Response.Redirect("https://localhost/JustEat.com/Home.aspx");
        }
        else
        {
            lblmessage.ForeColor = System.Drawing.Color.Red;
            lblmessage.Text = "Invalid User Name and/or Password";
        }

After User Entered their Credentials

if (Session["UserName"] != null)
        {
            string cs = ConfigurationManager.ConnectionStrings["DBCS"].ConnectionString;
            using (SqlConnection con = new SqlConnection(cs))
            {

                SqlDataAdapter da = new SqlDataAdapter("Select * from tblRegistration where Email='" + Session["UserName"] + "'", con);
                DataSet ds = new DataSet();
                da.Fill(ds);
                ddlLogin.Items.Clear();
                ddlLogin.Items.Add(ds.Tables[0].Rows[0]["Name"].ToString());
                ddlLogin.Items.Add(new ListItem() { Value = "Log", Text = "Log out" });
            }
        }

now the problem is that how can i make ddlLogin.Items.Add(new ListItem() { Value = "Log", Text = "Log out" }); this clickable.....

Answer 1

You can put this in the Page_Load of the master page. When the request is authenticated and there is no PostBack it clears the current items in the DropDownList and adds new ones.

if (Request.IsAuthenticated && !IsPostBack)
{
    ddlLogin.Items.Clear();
    ddlLogin.Items.Add(new ListItem() { Value = "-1", Text = "UserName" });
    ddlLogin.Items.Add(new ListItem() { Value = "1", Text = "Log out" });
}