ASP.Net: Showing buttons only to logged in users
SqlCommand query = new SqlCommand("Select Count(*) FROM Admin Where     username='"+Username.Text+"' AND password='"+Password.Text+"'", conn);

    conn.Open();
    int result = (int)query.ExecuteScalar();
    conn.Close();


    if (result > 0){
        Session["LoggedIn"] = true;
        Session["User"]=Username.Text;
    }
    else Session["LoggedIn"] = false;

if ((bool)Session["LoggedIn"]==true)) Button_dodaj_oglas.Visible = true;
    else Button_dodaj_oglas.Visible = false;

bool loggedIn = Session["LoggedIn"] != null && (bool)Session["LoggedIn"];
Button1.Visible = loggedIn;