ไม่ต้องการ Add Database ใส่ Combo แบบซ้ำๆ ที่ฟอร์มอืน

public static void DatabaseInCombobox(System.Windows.Forms.ComboBox cmb, string _SQL, string strConn, EnumConnectionType ConnectionType)
        {
            cmb.DataSource = GetTableForm(_SQL, strConn, ConnectionType);
        }
public static System.Data.DataTable GetTableForm(string _SQL, string strConn, EnumConnectionType ConnectionType )

        {
            
            System.Data.DataSet ds = new System.Data.DataSet();
            switch (ConnectionType)
            {
                case EnumConnectionType.ODBC:
                    System.Data.Odbc.OdbcConnection conn1 = new System.Data.Odbc.OdbcConnection(strConn);
                    conn1.Open();
                    System.Data.Odbc.OdbcDataAdapter adapter1 = new System.Data.Odbc.OdbcDataAdapter(_SQL, conn1);
                    adapter1.Fill(ds);
                    break;
                case EnumConnectionType.OLEDB:
                    System.Data.OleDb.OleDbConnection conn2 = new  System.Data.OleDb.OleDbConnection(strConn);
                    conn2.Open();
                    System.Data.OleDb.OleDbDataAdapter adapter2 = new  System.Data.OleDb.OleDbDataAdapter(_SQL, conn2);
                    adapter2.Fill(ds);
                    break;
                case EnumConnectionType.SqlClient:
                    System.Data.SqlClient.SqlConnection conn3 = new  System.Data.SqlClient.SqlConnection(strConn);
                    conn3.Open();
                    System.Data.SqlClient.SqlDataAdapter adapter3 = new  System.Data.SqlClient.SqlDataAdapter(_SQL, conn3);
                    adapter3.Fill(ds);

                    break;
            }

            return ds.Tables[0];

        }

DatabaseInCombobox(cmbSec,"SELECT Sec FROM tblSection",connString);