How Can : Fill ComboBox items with FieldNames from a Table?

مثال بسيط
..Caption Is The Solution  :*  ;)  

   string constr = "Integrated Security=SSPI;Persist Security Info=False;Initial Catalog=Library  System;Data Source=.";

            SqlConnection con = new SqlConnection(constr);
            con.Open();
            SqlCommand scm = new SqlCommand();
            scm.Connection = con;
             
            {
                 scm.CommandText = "select Subject,Title ,Author from Books ";
                DataTable dt = new DataTable();
                SqlDataAdapter adpt = new SqlDataAdapter(scm);
                adpt.Fill(dt);
           
               
                for (int i =0; i<dt  .Columns .Count  ; i++)
                {
                    comboBox1.Items.Add(dt.Columns[i  ].Caption);

                }