public void cargarColor(ComboBox comboBox1) { comboBox1.ToString(); CDConexion conexion = new CDConexion(); DataTable dt = new DataTable(); using (conexion.AbrirConexion()) { string query = "select * from coloresBuses order by color"; SqlCommand cmd = new SqlCommand(query, conexion.AbrirConexion()); SqlDataAdapter da = new SqlDataAdapter(cmd); da.Fill(dt); } comboBox1.DisplayMember = "color"; comboBox1.ValueMember = "id"; comboBox1.DataSource = dt; conexion.CerrarConexion(); }